Search results

Title: Integrative Analysis Of Lncrnas In Th17 Cell Lineage To Discover New Potential Biomarkers And Therapeutic Targets In Autoimmune Diseases.
Creator: Teimuri, Shohreh, Hosseini, Aref, Rezaenasab, Ahmad, Ghaedi, Kamran, Ghoveud, Elahe, Etemadifar, Masoud, Nasr-Esfahani, Mohammad Hossein, Megraw, Timothy L.
Abstract/Description: Th17 cells play a critical role in the pathogenesis of autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, and inflammatory bowel disease. Despite the extensive investigation into this T cell lineage, little is understood regarding the role of Th17 lineage-specific lncRNAs (long non-coding RNAs) > 200 nt. lncRNAs may influence disease through a variety of mechanisms; their expression could be regulated by SNPs. lncRNAs can...
Show moreTh17 cells play a critical role in the pathogenesis of autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, and inflammatory bowel disease. Despite the extensive investigation into this T cell lineage, little is understood regarding the role of Th17 lineage-specific lncRNAs (long non-coding RNAs) > 200 nt. lncRNAs may influence disease through a variety of mechanisms; their expression could be regulated by SNPs. lncRNAs can also affect the expression of neighboring genes or complementary miRNAs, and their expression may have lineage-specific patterns. In the system biology study presented here, the effective lncRNAs from different criteria were predicted for each autoimmune disease, and we then evaluated their expression levels in 50 MS patients compared to 25 controls using qRT-PCR. We identified changes in the expression levels of AL450992.2, AC009948.5, and RP11-98D18.3 as potential peripheral blood mononuclear cell (PBMC) biomarkers for MS among our studied lncRNAs in which co-expression analysis of AL450992.2 had the most AUCs, and the relationship to RORC was also assessed. We propose that the recurrently deregulated lncRNAs identified in this report could provide a valuable resource for studies aimed at delineating the relationship between functional lncRNAs and autoimmune disorders.
Show less
Date Issued: 2018-09-07
Identifier: FSU_libsubv1_wos_000443860200034, 10.1016/j.omtn.2018.05.022
Format: Citation

Title: Identification Of Anti-gram-negative Bacteria Agents Targeting The Interaction Between Ribosomal Proteins L12 And L10.
Creator: Wang, Weiwei, Liu, Chao, Zhu, Ningyu, Lin, Yuan, Jiang, Jiandong, Wang, Yanchang, Li, Yan, Si, Shuyi
Abstract/Description: Gram-negative bacteria have become the main pathogens and cause serious clinical problems with increased morbidity and mortality. However, the slow discovery of new antimicrobial agents is unable to meet the need for the treatment of bacterial infections caused by drug-resistant strains. The interaction of L12 and L10 is essential for ribosomal function and protein synthesis. In this study, a yeast two-hybrid system was established to successfully detect the interaction between L12 and L10...
Show moreGram-negative bacteria have become the main pathogens and cause serious clinical problems with increased morbidity and mortality. However, the slow discovery of new antimicrobial agents is unable to meet the need for the treatment of bacterial infections caused by drug-resistant strains. The interaction of L12 and L10 is essential for ribosomal function and protein synthesis. In this study, a yeast two-hybrid system was established to successfully detect the interaction between L12 and L10 proteins from gram-negative bacteria Escherichia coli, which allows us to screen compounds that specifically disrupt this interaction. With this system, we identified two compounds IMB-84 and IMB-87 that block L12-L10 interaction and show bactericidal activity against E. coli. We used glutathione-S-transferase (GST) pull-down and surface plasmon resonance (SPR) assays to demonstrate that these compounds disrupt L12-L10 interaction in vitro and the target of compounds was further confirmed by the overexpression of target proteins. Moreover, protein synthesis and elongation factor G-dependent GTPase activities are inhibited by two compounds. Therefore, we have identified two antibacterial agents that disrupt L12-L10 interaction by using yeast two-hybrid system. (C) 2018 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.
Show less
Date Issued: 2018-09-01
Identifier: FSU_libsubv1_wos_000445032400007, 10.1016/j.apsb.2018.07.006
Format: Citation

Title: An Hpsc-derived Tissue-resident Macrophage Model Reveals Differential Responses Of Macrophages To Zikv And Deny Infection.
Creator: Lang, Jianshe, Cheng, Yichen, Rolfe, Alyssa, Hammack, Christy, Vera, Daniel, Kyle, Kathleen, Wang, Jingying, Meissner, Torsten B., Ren, Yi, Cowan, Chad, Tang, Hengli
Abstract/Description: Zika virus (ZIKV) and dengue virus (DENV) are two closely related flaviviruses that lead to different clinical outcomes. The mechanism for the distinct pathogenesis of ZIKV and DENV is poorly understood. Here, we investigate ZIKV and DENV infection of macrophages using a human pluripotent stem cell (hPSC)-derived macrophage model and discover key virus-specific responses. ZIKV and DENV productively infect hPSC-derived macrophages. DENV, but not ZIKV, infection of macrophages strongly...
Show moreZika virus (ZIKV) and dengue virus (DENV) are two closely related flaviviruses that lead to different clinical outcomes. The mechanism for the distinct pathogenesis of ZIKV and DENV is poorly understood. Here, we investigate ZIKV and DENV infection of macrophages using a human pluripotent stem cell (hPSC)-derived macrophage model and discover key virus-specific responses. ZIKV and DENV productively infect hPSC-derived macrophages. DENV, but not ZIKV, infection of macrophages strongly activates macrophage migration inhibitory factor (MIF) secretion and decreases macrophage migration. Neutralization of MIF leads to improved migratory ability of DENV-infected macrophages. In contrast, ZIKV-infected macrophages exhibit prolonged migration and express low levels of pro-inflammatory cytokines and chemokines. Mechanistically, ZIKV disrupts the nuclear factor kappa B (NF-kappa B)-MIF positive feedback loop by inhibiting the NF-kappa B signaling pathway. Our results demonstrate the utility of hPSC-derived macrophages in infectious disease modeling and suggest that the distinct impact of ZIKV and DENV on macrophage immune response may underlie different pathogenesis of Zika and dengue diseases.
Show less
Date Issued: 2018-08-14
Identifier: FSU_libsubv1_wos_000441583100006, 10.1016/j.stemcr.2018.06.006
Format: Citation

Title: Expanded Coverage Of The 26s Proteasome Conformational Landscape Reveals Mechanisms Of Peptidase Gating.
Creator: Eisele, Markus R., Reed, Randi G., Rudack, Till, Schweitzer, Andreas, Beck, Florian, Nagy, Istvan, Pfeifer, Guenter, Plitzko, Juergen M., Baumeister, Wolfgang, Tomko, Robert J.,...
Show moreEisele, Markus R., Reed, Randi G., Rudack, Till, Schweitzer, Andreas, Beck, Florian, Nagy, Istvan, Pfeifer, Guenter, Plitzko, Juergen M., Baumeister, Wolfgang, Tomko, Robert J., Sakata, Eri
Show less
Abstract/Description: The proteasome is the central protease for intracellular protein breakdown. Coordinated binding and hydrolysis of ATP by the six proteasomal ATPase subunits induces conformational changes that drive the unfolding and translocation of substrates into the proteolytic 20S core particle for degradation. Here, we combine genetic and biochemical approaches with cryo-electron microscopy and integrative modeling to dissect the relationship between individual nucleotide binding events and proteasome...
Show moreThe proteasome is the central protease for intracellular protein breakdown. Coordinated binding and hydrolysis of ATP by the six proteasomal ATPase subunits induces conformational changes that drive the unfolding and translocation of substrates into the proteolytic 20S core particle for degradation. Here, we combine genetic and biochemical approaches with cryo-electron microscopy and integrative modeling to dissect the relationship between individual nucleotide binding events and proteasome conformational dynamics. We demonstrate unique impacts of ATP binding by individual ATPases on the proteasome conformational distribution and report two conformational states of the proteasome suggestive of a rotary ATP hydrolysis mechanism. These structures, coupled with functional analyses, reveal key roles for the ATPases Rpt1 and Rpt6 in gating substrate entry into the core particle. This deepened knowledge of proteasome conformational dynamics reveals key elements of intersubunit communication within the proteasome and clarifies the regulation of substrate entry into the proteolytic chamber.
Show less
Date Issued: 2018-07-31
Identifier: FSU_libsubv1_wos_000440377500019, 10.1016/j.celrep.2018.07.004
Format: Citation

Title: Impaired Antisaccades In Obsessive-compulsive Disorder: Evidence From Meta-analysis And A Large Empirical Study.
Creator: Bey, Katharina, Lennertz, Leonhard, Gruetzmann, Rosa, Heinzel, Stephan, Kaufmann, Christian, Klawohn, Julia, Riesel, Anja, Meyhoefer, Inga, Ettinger, Ulrich, Kathmann, Norbert,...
Show moreBey, Katharina, Lennertz, Leonhard, Gruetzmann, Rosa, Heinzel, Stephan, Kaufmann, Christian, Klawohn, Julia, Riesel, Anja, Meyhoefer, Inga, Ettinger, Ulrich, Kathmann, Norbert, Wagner, Michael
Show less
Abstract/Description: Increasing evidence indicates that patients with obsessive-compulsive disorder (OCD) exhibit alterations in fronto-striatal circuitry. Performance deficits in the antisaccade task would support this model, but results from previous small-scale studies have been inconclusive as either increased error rates, prolonged antisaccade latencies, both or neither have been reported in OCD patients. In order to address this issue, we investigated antisaccade performance in a large sample of OCD...
Show moreIncreasing evidence indicates that patients with obsessive-compulsive disorder (OCD) exhibit alterations in fronto-striatal circuitry. Performance deficits in the antisaccade task would support this model, but results from previous small-scale studies have been inconclusive as either increased error rates, prolonged antisaccade latencies, both or neither have been reported in OCD patients. In order to address this issue, we investigated antisaccade performance in a large sample of OCD patients (n = 169) and matched control subjects (n = 183). As impaired antisaccade performance constitutes a potential endophenotype of OCD, unaffected first-degree relatives of OCD patients (n = 100) were assessed, as well. Furthermore, we conducted a quantitative meta-analysis to integrate our data with previous findings. In the empirical study, OCD patients exhibited significantly increased antisaccade latencies, intra-subject variability (ISV) of antisaccade latencies, and antisaccade error rates. The latter effect was driven by errors with express latency (80-130 ms), as patients did not differ significantly from controls with regards to regular errors (>130 ms). Notably, unaffected relatives of OCD patients showed elevated antisaccade express error rates and increased ISV of antisaccade latencies, as well. Antisaccade performance was not associated with state anxiety within groups. Among relatives, however, we observed a significant correlation between antisaccade error rate and harm avoidance. Medication status of OCD patients, symptom severity, depressive comorbidity, comorbid anxiety disorders and OCD symptom dimensions did not significantly affect antisaccade performance. Meta-analysis of 10 previous and the present empirical study yielded a medium-sized effect (SMD = 0.48, p < 0.001) for higher error rates in OCD patients, while the effect for latencies did not reach significance owing to strong heterogeneity (SMD = 0.51, p = 0.069). Our results support the assumption of impaired antisaccade performance in OCD, although effects sizes were only moderately large. Furthermore, we provide the first evidence that increased antisaccade express error rates and ISV of antisaccade latencies may constitute endophenotypes of OCD. Findings regarding these more detailed antisaccade parameters point to potentially underlying mechanisms, such as early pre-stimulus inhibition of the superior colliculus.
Show less
Date Issued: 2018-06-29
Identifier: FSU_libsubv1_wos_000436854900001, 10.3389/fpsyt.2018.00284
Format: Citation

Title: Diverse Intrinsic Properties Shape Functional Phenotype Of Low-frequency Neurons In The Auditory Brainstem.
Creator: Hong, Hui, Wang, Xiaoyu, Lu, Ting, Zorio, Diego A. R., Wang, Yuan, Sanchez, Jason Tait
Abstract/Description: In the auditory system, tonotopy is the spatial arrangement of where sounds of different frequencies are processed. Defined by the organization of neurons and their inputs, tonotopy emphasizes distinctions in neuronal structure and function across topographic gradients and is a common feature shared among vertebrates. In this study we characterized action potential firing patterns and ion channel properties from neurons located in the extremely low-frequency region of the chicken nucleus...
Show moreIn the auditory system, tonotopy is the spatial arrangement of where sounds of different frequencies are processed. Defined by the organization of neurons and their inputs, tonotopy emphasizes distinctions in neuronal structure and function across topographic gradients and is a common feature shared among vertebrates. In this study we characterized action potential firing patterns and ion channel properties from neurons located in the extremely low-frequency region of the chicken nucleus magnocellularis (NM), an auditory brainstem structure. We found that NM neurons responsible for encoding the lowest sound frequencies (termed NMc neurons) have enhanced excitability and fired bursts of action potentials to sinusoidal inputs <= 10 Hz; a distinct firing pattern compared to higher-frequency neurons. This response property was due to lower amounts of voltage dependent potassium (K-v) conductances, unique combination of K-v subunits and specialized sodium (Na-v) channel properties. Particularly, NMc neurons had significantly lower K(v)1 and K(v)3 currents, but higher K(v)2current. NMc neurons also showed larger and faster transient Nav current (I-NaT) with different voltage dependence of inactivation from higher-frequency neurons. In contrast, significantly smaller resurgent sodium current (I-NaR) was present in NMc with kinetics and voltage dependence that differed from higher-frequency neurons. Immunohistochemistry showed expression of Na(v)1.6 channel subtypes across the tonotopic axis. However, various immunoreactive patterns were observed between regions, likely underlying some tonotopic differences in I-N(aT) and I-NaR. Finally, using pharmacology and computational modeling, we concluded that K(v)3, K(v)2 channels and I-NaR work synergistically to regulate burst firing in NMc.
Show less
Date Issued: 2018-06-26
Identifier: FSU_libsubv1_wos_000436338700001, 10.3389/fncel.2018.00175
Format: Citation

Title: Fine-sampled Photographic Quantitation of Dermal Wound Healing Senescence in Aged BALB/cByJ Mice and Therapeutic Intervention with FGF-1: Novel photographic quantitation of dermal healing.
Creator: Mellers, Alana, Tenorio, Connie, Lacatusu, Diana, Powell, Brett, Patel, Bhavi, Harper, Kathleen, Blaber, Michael
Abstract/Description: Objective: Determine quantitative parameters of dermal wound healing senescence in aged BALB/cByJ mice (an important animal model of aging) and evaluate the potential for therapeutic intervention by fibroblast growth factor-1 (FGF-1). Approach: Utilize a novel, non-invasive, fine-sampled photographic methodology to quantify wound healing parameters for healing phases from wounding through to wound closure. Results: Parameters associated with key healing phases were quantified and compared for...
Show moreObjective: Determine quantitative parameters of dermal wound healing senescence in aged BALB/cByJ mice (an important animal model of aging) and evaluate the potential for therapeutic intervention by fibroblast growth factor-1 (FGF-1). Approach: Utilize a novel, non-invasive, fine-sampled photographic methodology to quantify wound healing parameters for healing phases from wounding through to wound closure. Results: Parameters associated with key healing phases were quantified and compared for non-aged and aged cohorts of both sexes. The results identify a sexual dimorphism in dermal wound healing, with non-aged females exhibiting a greater overall healing efficiency compared to males. This enhanced healing in females, however, senesces with age such that healing parameters for aged males and females are statistically indistinguishable. Topical application of FGF-1 was identified as an effective therapeutic intervention to treat dermal healing senescence in aged females. Innovation: The FGF intervention is being analyzed using a new, recently published model. This approach significantly increases the amount of pre-clinical animal data obtainable in wound healing studies, minimizes cohort number compared to (lethal) histological studies, and permits a direct statistical comparison between different healing studies. Conclusion: Quantitative parameters of dermal wound healing, obtained from non-invasive fine-sampled photographic data, identify topical FGF-1 as an effective therapeutic to treat the senescence of dermal healing present in aged female BALB/cByJ mice.
Show less
Date Issued: 2018-06-25
Identifier: FSU_libsubv1_scholarship_submission_1529889363_21ee7933
Format: Citation

Title: Attention And Working Memory Deficits In A Perinatal Nicotine Exposure Mouse Model.
Creator: Zhang, Lin, Spencer, Thomas J., Biederman, Joseph, Bhide, Pradeep G.
Abstract/Description: Background Cigarette smoking by pregnant women is associated with a significant increase in the risk for cognitive disorders in their children. Preclinical models confirm this risk by showing that exposure of the developing brain to nicotine produces adverse behavioral outcomes. Here we describe behavioral phenotypes resulting from perinatal nicotine exposure in a mouse model, and discuss our findings in the context of findings from previously published studies using preclinical models of...
Show moreBackground Cigarette smoking by pregnant women is associated with a significant increase in the risk for cognitive disorders in their children. Preclinical models confirm this risk by showing that exposure of the developing brain to nicotine produces adverse behavioral outcomes. Here we describe behavioral phenotypes resulting from perinatal nicotine exposure in a mouse model, and discuss our findings in the context of findings from previously published studies using preclinical models of developmental nicotine exposure. Methodology/Principal findings Female C57BI/6 mice received drinking water containing nicotine (100pg/ml) + saccharin (2%) starting 3 weeks prior to breeding and continuing throughout pregnancy, and until 3 weeks postpartum. Over the same period, female mice in two control groups received drinking water containing saccharin (2%) or plain drinking water. Offspring from each group were weaned at 3-weeks of age and subjected to behavioral analyses at 3 months of age. We examined spontaneous locomotor activity, anxiety-like behavior, spatial working memory, object based attention, recognition memory and impulsive-like behavior. We found significant deficits in attention and working memory only in male mice, and no significant changes in the other behavioral phenotypes in male or female mice. Exposure to saccharin alone did not produce significant changes in either sex. Conclusion/Significance The perinatal nicotine exposure produced significant deficits in attention and working memory in a sex-dependent manner in that the male but not female offspring displayed these behaviors. These behavioral phenotypes are associated with attention deficit hyperactivity disorder (ADHD) and have been reported in other studies that used pre-or perinatal nicotine exposure. Therefore, we suggest that preclinical models of developmental nicotine exposure could be useful tools for modeling ADHD and related disorders.
Show less
Date Issued: 2018-05-24
Identifier: FSU_libsubv1_wos_000433084300123, 10.1371/journal.pone.0198064
Format: Citation

Title: Mtor Signaling Regulates Central And Peripheral Circadian Clock Function.
Creator: Ramanathan, Chidambaram, Kathale, Nimish D., Liu, Dong, Lee, Choogon, Freeman, David A., Hogenesch, John B., Cao, Ruifeng, Liu, Andrew C.
Abstract/Description: The circadian clock coordinates physiology and metabolism. mTOR (mammalianmechanistic target of rapamycin) is a major intracellular sensor that integrates nutrient and energy status to regulate protein synthesis, metabolism, and cell growth. Previous studies have identified a key role for mTOR in regulating photic entrainment and synchrony of the central circadian clock in the suprachiasmatic nucleus (SCN). Given that mTOR activities exhibit robust circadian oscillations in a variety of...
Show moreThe circadian clock coordinates physiology and metabolism. mTOR (mammalianmechanistic target of rapamycin) is a major intracellular sensor that integrates nutrient and energy status to regulate protein synthesis, metabolism, and cell growth. Previous studies have identified a key role for mTOR in regulating photic entrainment and synchrony of the central circadian clock in the suprachiasmatic nucleus (SCN). Given that mTOR activities exhibit robust circadian oscillations in a variety of tissues and cells including the SCN, here we continued to investigate the role of mTOR in orchestrating autonomous clock functions in central and peripheral circadian oscillators. Using a combination of genetic and pharmacological approaches we show that mTOR regulates intrinsic clock properties including period and amplitude. In peripheral clock models of hepatocytes and adipocytes, mTOR inhibition lengthens period and dampens amplitude, whereas mTOR activation shortens period and augments amplitude. Constitutive activation of mTOR in Tsc2(-/-)fibroblasts elevates levels of core clock proteins, including CRY1, BMAL1 and CLOCK. Serum stimulation induces CRY1 upregulation in fibroblasts in an mTOR-dependent but Bmal1- and Period-independent manner. Consistent with results from cellular clock models, mTOR perturbation also regulates period and amplitude in the ex vivo SCN and liver clocks. Further, mTOR heterozygous mice show lengthened circadian period of locomotor activity in both constant darkness and constant light. Together, these results support a significant role for mTOR in circadian timekeeping and in linking metabolic states to circadian clock functions.
Show less
Date Issued: 2018-05-01
Identifier: FSU_libsubv1_wos_000434016500019, 10.1371/journal.pgen.1007369
Format: Citation

Title: Microrna-22 Inhibits The Proliferation And Migration, And Increases The Cisplatin Sensitivity, Of Osteosarcoma Cells.
Creator: Zhou, Xiang, Natino, Dimple, Zhai, Xu, Gao, Zhongyang, He, Xijing
Abstract/Description: Osteosarcoma (OS) is the major type of primary bone tumor and is associated with a poor prognosis due to chemotherapy resistance. Accumulating evidence indicates that microRNAs (miRNAs/miRs) may influence the tumor progression of OS and cell sensitivity to chemotherapy. In the present study, a total of 7 patients with OS and 7 healthy volunteers were recruited. Reverse transcription-quantitative polymerase chain reaction and ELISA were performed to determine the expression of miRNAs and mRNAs...
Show moreOsteosarcoma (OS) is the major type of primary bone tumor and is associated with a poor prognosis due to chemotherapy resistance. Accumulating evidence indicates that microRNAs (miRNAs/miRs) may influence the tumor progression of OS and cell sensitivity to chemotherapy. In the present study, a total of 7 patients with OS and 7 healthy volunteers were recruited. Reverse transcription-quantitative polymerase chain reaction and ELISA were performed to determine the expression of miRNAs and mRNAs in the serum of participants. Furthermore, the biological function of miR-22 and S100A11 was examined in MG-63 cells using Cell Counting Kit-8 assays, Transwell migration assays and western blot analysis to determine the effects on cell proliferation, migration and protein expression, respectively, while MG-63 cell sensitivity to cisplatin was assessed by measuring cell viability following cisplatin treatment and calculating the half maximal inhibitory concentration (IC50). Additionally, the association between miR-22 and S100 calcium-binding protein A11 (S100A11) was validated using a luciferase reporter assay. The results demonstrated that miR-22 expression was significantly reduced in patients with OS and the MG-63 OS cell line, compared with healthy volunteers and the normal osteoblast hFOB 1.19 cell line, respectively, while the expression of S100A11 was negatively associated with miR-22 levels in the MG-63 cell line. Furthermore, overexpression of miR-22 inhibited the proliferation and migratory ability of MG-63 cells, and increased the sensitivity of MG-63 cells to cisplatin treatment; however, overexpression of S100A11 partially attenuated the alterations in proliferation, migratory ability and chemosensitivity that were induced by miR-22 overexpression. In addition, it was confirmed that S100A11 is a direct target gene of miR-22 in MG-63 cells. In conclusion, to the best of our knowledge, the present study is the first to demonstrate that miR-22 may be a promising therapeutic target and may have potential as part of a combination treatment alongside chemotherapeutic agents for OS.
Show less
Date Issued: 2018-05-01
Identifier: FSU_libsubv1_wos_000430556800125, 10.3892/mmr.2018.8790
Format: Citation

Title: A Mathematical Model for the Determination of Mouse Excisional Wound Healing Parameters from Photographic Data.
Creator: Cogan, Nicholas G, Mellers, Alana, Patel, Bhavi, Powell, Brett, Aggarwal, Manu, Harper, Kathleen M, Blaber, Michael
Abstract/Description: We present a mathematical model to quantify parameters of mouse excisional wound healing from photographic data. The equation is a piecewise linear function in log scale that includes key parameters of initial wound radius (R0), an initial wound stasis phase (Ti), and time to wound closure (Tc); subsequently, these terms permit calculation of a latter active proliferative phase (Tp), and the healing rate (HR) during this active phase. A daily photographic record of wound healing (utilizing 6...
Show moreWe present a mathematical model to quantify parameters of mouse excisional wound healing from photographic data. The equation is a piecewise linear function in log scale that includes key parameters of initial wound radius (R0), an initial wound stasis phase (Ti), and time to wound closure (Tc); subsequently, these terms permit calculation of a latter active proliferative phase (Tp), and the healing rate (HR) during this active phase. A daily photographic record of wound healing (utilizing 6 mm diameter splinted excisional wounds) permits the necessary sampling for robust parameter refinement. When implemented with an automated nonlinear fitting routine, the healing parameters are determined in an operator-independent (i.e. unbiased) manner. The model was evaluated using photographic data from a splinted excisional surgical procedure involving several different mouse cohorts. Model fitting demonstrates excellent coefficients of determination (R2) in each case. The model thus permits quantitation of key parameters of excisional wound healing, from initial wounding through to wound closure, from photographic data.
Show less
Date Issued: 2018-04-17
Identifier: FSU_libsubv1_scholarship_submission_1522454139_52860c9c, 10.1111/wrr.12634
Format: Citation

Title: Investigating the Dynamics and Polyanion Binding Sites of Fibroblast Growth Factor-1 Using Hydrogen-Deuterium Exchange Mass Spectrometry.
Creator: Angalakurthi, Siva K, Tenorio, Connie A, Blaber, Michael, Middaugh, Russell
Abstract/Description: In this study, we examined the local dynamics of acidic fibroblast growth factor (FGF-1) as well as the binding sites of various polyanions including poly-sulfates (heparin and low MW heparin) and poly-phosphates (phytic acid and ATP) using hydrogen-deuterium exchange mass spectrometry (HX-MS). For local dynamics, results are analyzed at the peptide level as well as in terms of buried amides employing crystallographic B-factors and compared with a residue level heat map generated from HX-MS...
Show moreIn this study, we examined the local dynamics of acidic fibroblast growth factor (FGF-1) as well as the binding sites of various polyanions including poly-sulfates (heparin and low MW heparin) and poly-phosphates (phytic acid and ATP) using hydrogen-deuterium exchange mass spectrometry (HX-MS). For local dynamics, results are analyzed at the peptide level as well as in terms of buried amides employing crystallographic B-factors and compared with a residue level heat map generated from HX-MS results. Results show that strand 4 and 5 and the turn between them to be the most flexible regions as was previously seen by NMR. On the other hand, the C-terminal strands 8, 9 and 10 appear to be more rigid which is also consistent with crystallographic B-factors as well as local dynamics studies conducted by NMR. Crystal structures of FGF-1 in complex with heparin have shown that heparin binds to N-terminal Asn18 and to C-terminal Lys105, Tryp107, Lys112, Lys113, Arg119, Pro121, Arg122, Gln127 and Lys128 indicating electrostatic forces as dominant interactions. Heparin binding as determined by HX-MS is consistent with crystallography data. Previous studies have also shown that other polyanions including low MW heparin, phytic acid and ATP dramatically increase the thermal stability of FGF-1. Using HX-MS, we find other poly anions tested bind in a similar manner to heparin, primarily targeting the turns in the lysine rich C-terminal region of FGF-1 along with two distinct N-terminal regions that contains lysines and arginines/ histidines. This confirms the interactions between FGF-1 and polyanions are primary directed by electrostatics.
Show less
Date Issued: 2018-04-05
Identifier: FSU_libsubv1_scholarship_submission_1523040928_8f170751
Format: Citation

Title: Tetraspanin Cd63 Bridges Autophagic And Endosomal Processes To Regulate Exosomal Secretion And Intracellular Signaling Of Epstein-barr Virus Lmp1.
Creator: Hurwitz, Stephanie N., Cheerathodi, Mujeeb R., Nkosi, Dingani, York, Sara B., Meckes, David G.
Abstract/Description: The tetraspanin protein CD63 has been recently described as a key factor in extracellular vesicle (EV) production and endosomal cargo sorting. In the context of Epstein-Barr virus (EBV) infection, CD63 is required for the efficient packaging of the major viral oncoprotein latent membrane protein 1 (LMP1) into exosomes and other EV populations and acts as a negative regulator of LMP1 intracellular signaling. Accumulating evidence has also pointed to intersections of the endosomal and autophagy...
Show moreThe tetraspanin protein CD63 has been recently described as a key factor in extracellular vesicle (EV) production and endosomal cargo sorting. In the context of Epstein-Barr virus (EBV) infection, CD63 is required for the efficient packaging of the major viral oncoprotein latent membrane protein 1 (LMP1) into exosomes and other EV populations and acts as a negative regulator of LMP1 intracellular signaling. Accumulating evidence has also pointed to intersections of the endosomal and autophagy pathways in maintaining cellular secretory processes and as sites for viral assembly and replication. Indeed, LMP1 can activate the mammalian target of rapamycin (mTOR) pathway to suppress host cell autophagy and facilitate cell growth and proliferation. Despite the growing recognition of cross talk between endosomes and autophagosomes and its relevance to viral infection, little is understood about the molecular mechanisms governing endosomal and autophagy convergence. Here, we demonstrate that CD63-dependent vesicle protein secretion directly opposes intracellular signaling activation downstream of LMP1, including mTOR-associated proteins. Conversely, disruption of normal autolysosomal processes increases LMP1 secretion and dampens signal transduction by the viral protein. Increases in mTOR activation following CD63 knockout are coincident with the development of serum-dependent autophagic vacuoles that are acidified in the presence of high LMP1 levels. Altogether, these findings suggest a key role of CD63 in regulating the interactions between endosomal and autophagy processes and limiting cellular signaling activity in both noninfected and virally infected cells. IMPORTANCE The close connection between extracellular vesicles and viruses is becoming rapidly and more widely appreciated. EBV, a human gamma herpesvirus that contributes to the progression of a multitude of lymphomas and carcinomas in immunocompromised or genetically susceptible populations, packages its major oncoprotein, LMP1, into vesicles for secretion. We have recently described a role of the host cell protein CD63 in regulating intracellular signaling of the viral oncoprotein by shuttling LMP1 into exosomes. Here, we provide strong evidence of the utility of CD63-dependent EVs in regulating global intracellular signaling, including mTOR activation by LMP1. We also demonstrate a key role of CD63 in coordinating endosomal and autophagic processes to regulate LMP1 levels within the cell. Overall, this study offers new insights into the complex intersection of cellular secretory and degradative mechanisms and the implications of these processes in viral replication.
Show less
Date Issued: 2018-03
Identifier: FSU_libsubv1_wos_000424744800023, 10.1128/JVI.01969-17
Format: Citation

Title: The Absence Of Specific Yeast Heat-shock Proteins Leads To Abnormal Aggregation And Compromised Autophagic Clearance Of Mutant Huntingtin Proteins.
Creator: Higgins, Ryan, Kabbaj, Marie-Helene, Hatcher, Alexa, Wang, Yanchang
Abstract/Description: The functionality of a protein depends on its correct folding, but newly synthesized proteins are susceptible to aberrant folding and aggregation. Heat shock proteins (HSPs) function as molecular chaperones that aid in protein folding and the degradation of misfolded proteins. Trinucleotide (CAG) repeat expansion in the Huntingtin gene (HTT) results in the expression of misfolded Huntingtin protein (Htt), which contributes to the development of Huntington's disease. We previously found that...
Show moreThe functionality of a protein depends on its correct folding, but newly synthesized proteins are susceptible to aberrant folding and aggregation. Heat shock proteins (HSPs) function as molecular chaperones that aid in protein folding and the degradation of misfolded proteins. Trinucleotide (CAG) repeat expansion in the Huntingtin gene (HTT) results in the expression of misfolded Huntingtin protein (Htt), which contributes to the development of Huntington's disease. We previously found that the degradation of mutated Htt with polyQ expansion (Htt103QP) depends on both ubiquitin proteasome system and autophagy. However, the role of heat shock proteins in the clearance of mutated Htt remains poorly understood. Here, we report that cytosolic Hsp70 (Ssa family), its nucleotide exchange factors (Sse1 and Fes1), and a Hsp40 co-chaperone (Ydj1) are required for inclusion body formation of Htt103QP proteins and their clearance via autophagy. Extended induction of Htt103QPGFP leads to the formation of a single inclusion body in wild-type yeast cells, but mutant cells lacking these HSPs exhibit increased number of Htt103QP aggregates. Most notably, we detected more aggregated forms of Htt103QP in sse1 Delta. mutant cells using an agarose gel assay. Increased protein aggregates are also observed in these HSP mutants even in the absence Htt103QP overexpression. Importantly, these HSPs are required for autophagy- mediated Htt103QP clearance, but are less critical for proteasome-dependent degradation. These findings suggest a chaperone network that facilitates inclusion body formation of misfolded proteins and the subsequent autophagic clearance.
Show less
Date Issued: 2018-01-18
Identifier: FSU_libsubv1_wos_000422749500056, 10.1371/journal.pone.0191490
Format: Citation

Title: Troponin Through The Looking-glass: Emerging Roles Beyond Regulation Of Striated Muscle Contraction.
Creator: Johnston, Jamie R., Chase, P. Bryant, Pinto, Jose Renato
Abstract/Description: Troponin is a heterotrimeric Ca2+-binding protein that has a well-established role in regulating striated muscle contraction. However, mounting evidence points to novel cellular functions of troponin, with profound implications in cancer, cardiomyopathy pathogenesis and skeletal muscle aging. Here, we highlight the non-canonical roles and aberrant expression patterns of troponin beyond the sarcomeric milieu. Utilizing bioinformatics tools and online databases, we also provide pathway,...
Show moreTroponin is a heterotrimeric Ca2+-binding protein that has a well-established role in regulating striated muscle contraction. However, mounting evidence points to novel cellular functions of troponin, with profound implications in cancer, cardiomyopathy pathogenesis and skeletal muscle aging. Here, we highlight the non-canonical roles and aberrant expression patterns of troponin beyond the sarcomeric milieu. Utilizing bioinformatics tools and online databases, we also provide pathway, subcellular localization, and protein-protein/DNA interaction analyses that support a role for troponin in multiple subcellular compartments. This emerging knowledge challenges the conventional view of troponin as a sarcomere-specific protein exclusively involved in muscle contraction and may transform the way we think about sarcomeric proteins, particularly in the context of human disease and aging.
Show less
Date Issued: 2018-01-02
Identifier: FSU_libsubv1_wos_000419615500116, 10.18632/oncotarget.22879
Format: Citation

Title: The Folding Nucleus Structure Persists in Thermally-Aggregated FGF-1.
Creator: Longo, Liam, Gao, Yuan, Tenorio, Connie, Wang, Gan, Paravastu, Anant, Blaber, Michael
Abstract/Description: An efficient protein folding pathway leading to target structure, and the avoidance of aggregation, is essential to protein evolution and de novo design; however, design details to achieve efficient folding and avoid aggregation are poorly understood. We report characterization of the thermally-induced aggregate of fibroblast growth factor-1 (FGF-1), a small globular protein, by solid-state NMR. NMR spectra are consistent with residual structure in the aggregate and provide evidence of a...
Show moreAn efficient protein folding pathway leading to target structure, and the avoidance of aggregation, is essential to protein evolution and de novo design; however, design details to achieve efficient folding and avoid aggregation are poorly understood. We report characterization of the thermally-induced aggregate of fibroblast growth factor-1 (FGF-1), a small globular protein, by solid-state NMR. NMR spectra are consistent with residual structure in the aggregate and provide evidence of a structured region that corresponds to the region of the folding nucleus. NMR data on aggregated FGF-1 also indicate the presence of unstructured regions that exhibit hydration-dependent dynamics and suggest that unstructured regions of aggregated FGF-1 lie outside the folding nucleus. Since it is known that regions outside the folding nucleus fold late in the folding pathway, we postulate that these regions unfold early in the unfolding pathway and that the partially folded state is more prone to intermolecular aggregation. This interpretation is further supported by comparison with a designed protein that shares the same FGF-1 folding nucleus sequence, but has different 1° structure outside the folding nucleus, and does not thermally aggregate. The results suggest that design of an efficient folding nucleus, and the avoidance of aggregation in the folding pathway, are potentially separable design criteria – the latter of which could principally focus upon the physicochemical properties of 1° structure outside the folding nucleus.
Show less
Date Issued: 2017-10-23
Identifier: FSU_libsubv1_scholarship_submission_1509376995_85b5a7ca, 10.1002/pro.3332
Format: Citation

Title: Proteomic analyses of nucleus laminaris identified candidate targets of the fragile X mental retardation protein.
Creator: Sakano, Hitomi, Zorio, Diego A R, Wang, Xiaoyu, Ting, Ying S, Noble, William S, MacCoss, Michael J, Rubel, Edwin W, Wang, Yuan
Abstract/Description: The avian nucleus laminaris (NL) is a brainstem nucleus necessary for binaural processing, analogous in structure and function to the mammalian medial superior olive. In chickens (Gallus gallus), NL is a well-studied model system for activity-dependent neural plasticity. Its neurons have bipolar extension of dendrites, which receive segregated inputs from two ears and display rapid and compartment-specific reorganization in response to unilateral changes in auditory input. More recently,...
Show moreThe avian nucleus laminaris (NL) is a brainstem nucleus necessary for binaural processing, analogous in structure and function to the mammalian medial superior olive. In chickens (Gallus gallus), NL is a well-studied model system for activity-dependent neural plasticity. Its neurons have bipolar extension of dendrites, which receive segregated inputs from two ears and display rapid and compartment-specific reorganization in response to unilateral changes in auditory input. More recently, fragile X mental retardation protein (FMRP), an RNA-binding protein that regulates local protein translation, has been shown to be enriched in NL dendrites, suggesting its potential role in the structural dynamics of these dendrites. To explore the molecular role of FMRP in this nucleus, we performed proteomic analysis of NL, using micro laser capture and liquid chromatography tandem mass spectrometry. We identified 657 proteins, greatly represented in pathways involved in mitochondria, translation and metabolism, consistent with high levels of activity of NL neurons. Of these, 94 are potential FMRP targets, by comparative analysis with previously proposed FMRP targets in mammals. These proteins are enriched in pathways involved in cellular growth, cellular trafficking and transmembrane transport. Immunocytochemistry verified the dendritic localization of several proteins in NL. Furthermore, we confirmed the direct interaction of FMRP with one candidate, RhoC, by in vitro RNA binding assays. In summary, we provide a database of highly expressed proteins in NL and in particular a list of potential FMRP targets, with the goal of facilitating molecular characterization of FMRP signaling in future studies.
Show less
Date Issued: 2017-10-15
Identifier: FSU_pmch_28685837, 10.1002/cne.24281, PMC5564178, 28685837, 28685837
Format: Citation

Title: Heterogeneous organization and connectivity of the chicken auditory thalamus (Gallus gallus).
Creator: Wang, Yuan, Zorio, Diego A R, Karten, Harvey J
Abstract/Description: The auditory ascending system contains parallel pathways in vertebrate brains. In chickens (Gallus gallus), three pathways arise from nucleus laminaris (NL), nucleus angularis (NA), and regio intermedius (RI) in the brainstem, innervating three subdivisions of the nucleus mesencephalicus lateralis pars dorsalis (MLd) in the midbrain. The current study reveals the segregation of these pathways in their subsequent projections to the nucleus ovoidalis (Ov) in the thalamus. Based on...
Show moreThe auditory ascending system contains parallel pathways in vertebrate brains. In chickens (Gallus gallus), three pathways arise from nucleus laminaris (NL), nucleus angularis (NA), and regio intermedius (RI) in the brainstem, innervating three subdivisions of the nucleus mesencephalicus lateralis pars dorsalis (MLd) in the midbrain. The current study reveals the segregation of these pathways in their subsequent projections to the nucleus ovoidalis (Ov) in the thalamus. Based on cytoarchitecture and myelin distribution, we identified seven Ov subregions, including five neuronal clusters within the Ov proper, the nucleus semilunaris parovoidalis (SPO), and the circum-ovoidalis (cOv). Immunocytochemistry further revealed that a ventromedial cluster of the Ov proper (Ovvm) contains unique cell types expressing α8 subunit nicotinic acetylcholine receptor, while SPO and cOv are characterized with expression of calcitonin-gene-related peptide and cholecystokinin. Tract tracing studies demonstrated that Ovvm is a major target of the NL-recipient zone of MLd, while the RI-recipient zone of MLd predominantly projects to a ventrolateral cluster of the Ov proper. Afferent inputs to the remaining regions of the Ov proper mostly arise from the NA-recipient zone of MLd. SPO and cOv receive a projection from the surrounding areas of MLd, named the nucleus intercollicularis. Importantly, the Ov proper, SPO and cOv all project to the Field L2 in the forebrain, the avian auditory cortex. Taken together, these results demonstrate that the avian auditory thalamus is a structurally and functionally heterogeneous structure, implicating an important role in generating novel representations for specific acoustic features.
Show less
Date Issued: 2017-10-01
Identifier: FSU_pmch_28614906, 10.1002/cne.24262, PMC5558206, 28614906, 28614906
Format: Citation

Title: Integrin β3/Akt signaling contributes to platelet-induced hemangioendothelioma growth.
Creator: Gu, Rui, Sun, Xin, Chi, Yijie, Zhou, Qishuang, Xiang, Hongkai, Bosco, Dale B, Lai, Xinhe, Qin, Caixia, So, Kwok-Fai, Ren, Yi, Chen, Xiao-Ming
Abstract/Description: Hemangioendothelioma (HE) is a type of angiomatous lesions that features endothelial cell proliferation. Understanding the mechanisms orchestrating HE angiogenesis can provide therapeutic insights. It has been shown that platelets can support normal and malignant endothelial cells during angiogenesis. Using the mouse endothelial-derived EOMA cell line as a model of HE, we explored the regulatory effect of platelets. We found that platelets stimulated EOMA proliferation but did not mitigate...
Show moreHemangioendothelioma (HE) is a type of angiomatous lesions that features endothelial cell proliferation. Understanding the mechanisms orchestrating HE angiogenesis can provide therapeutic insights. It has been shown that platelets can support normal and malignant endothelial cells during angiogenesis. Using the mouse endothelial-derived EOMA cell line as a model of HE, we explored the regulatory effect of platelets. We found that platelets stimulated EOMA proliferation but did not mitigate apoptosis. Furthermore, direct platelet-EOMA cell contact was required and the proliferation was mediated via integrin β3/Akt signaling in EOMA cells. SiRNA knockdown of integrin β3 and inhibition of Akt activity significantly abolished platelet-induced EOMA cell proliferation in vitro and tumor development in vivo. These results provide a new mechanism by which platelets support HE progression and suggest integrin β3 as a potential target to treat HE.
Show less
Date Issued: 2017-07-25
Identifier: FSU_pmch_28744026, 10.1038/s41598-017-06927-0, PMC5527091, 28744026, 28744026, 10.1038/s41598-017-06927-0
Format: Citation

Title: Genotype-specific pathogenic effects in human dilated cardiomyopathy.
Creator: Bollen, Ilse A E, Schuldt, Maike, Harakalova, Magdalena, Vink, Aryan, Asselbergs, Folkert W, Pinto, Jose R, Krüger, Martina, Kuster, Diederik W D, van der Velden, Jolanda
Abstract/Description: Mutations in genes encoding cardiac troponin I (TNNI3) and cardiac troponin T (TNNT2) caused altered troponin protein stoichiometry in patients with dilated cardiomyopathy. TNNI3p.98trunc resulted in haploinsufficiency, increased Ca(2+) -sensitivity and reduced length-dependent activation. TNNT2p.K217del caused increased passive tension. A mutation in the gene encoding Lamin A/C (LMNAp.R331Q ) led to reduced maximal force development through secondary disease remodelling in patients suffering...
Show moreMutations in genes encoding cardiac troponin I (TNNI3) and cardiac troponin T (TNNT2) caused altered troponin protein stoichiometry in patients with dilated cardiomyopathy. TNNI3p.98trunc resulted in haploinsufficiency, increased Ca(2+) -sensitivity and reduced length-dependent activation. TNNT2p.K217del caused increased passive tension. A mutation in the gene encoding Lamin A/C (LMNAp.R331Q ) led to reduced maximal force development through secondary disease remodelling in patients suffering from dilated cardiomyopathy. Our study shows that different gene mutations induce dilated cardiomyopathy via diverse cellular pathways. Dilated cardiomyopathy (DCM) can be caused by mutations in sarcomeric and non-sarcomeric genes. In this study we defined the pathogenic effects of three DCM-causing mutations: the sarcomeric mutations in genes encoding cardiac troponin I (TNNI3p.98truncation ) and cardiac troponin T (TNNT2p.K217deletion ; also known as the p.K210del) and the non-sarcomeric gene mutation encoding lamin A/C (LMNAp.R331Q ). We assessed sarcomeric protein expression and phosphorylation and contractile behaviour in single membrane-permeabilized cardiomyocytes in human left ventricular heart tissue. Exchange with recombinant troponin complex was used to establish the direct pathogenic effects of the mutations in TNNI3 and TNNT2. The TNNI3p.98trunc and TNNT2p.K217del mutation showed reduced expression of troponin I to 39% and 51%, troponin T to 64% and 53%, and troponin C to 73% and 97% of controls, respectively, and altered stoichiometry between the three cardiac troponin subunits. The TNNI3p.98trunc showed pure haploinsufficiency, increased Ca(2+) -sensitivity and impaired length-dependent activation. The TNNT2p.K217del mutation showed a significant increase in passive tension that was not due to changes in titin isoform composition or phosphorylation. Exchange with wild-type troponin complex corrected troponin protein levels to 83% of controls in the TNNI3p.98trunc sample. Moreover, upon exchange all functional deficits in the TNNI3p.98trunc and TNNT2p.K217del samples were normalized to control values confirming the pathogenic effects of the troponin mutations. The LMNAp.R331Q mutation resulted in reduced maximal force development due to disease remodelling. Our study shows that different gene mutations induce DCM via diverse cellular pathways.
Show less
Date Issued: 2017-07-15
Identifier: FSU_pmch_28436080, 10.1113/JP274145, PMC5509872, 28436080, 28436080
Format: Citation

Title: Locomotor sensitization to intermittent ketamine administration is associated with nucleus accumbens plasticity in male and female rats.
Creator: Strong, C E, Schoepfer, K J, Dossat, A M, Saland, S K, Wright, K N, Kabbaj, M
Abstract/Description: Clinical evidence suggests superior antidepressant response over time with a repeated, intermittent ketamine treatment regimen as compared to a single infusion. However, the club drug ketamine is commonly abused. Therefore, the abuse potential of repeated ketamine injections at low doses needs to be investigated. In this study, we investigated the abuse potential of repeated exposure to either 0, 2.5, or 5 mg/kg ketamine administered once weekly for seven weeks. Locomotor activity and...
Show moreClinical evidence suggests superior antidepressant response over time with a repeated, intermittent ketamine treatment regimen as compared to a single infusion. However, the club drug ketamine is commonly abused. Therefore, the abuse potential of repeated ketamine injections at low doses needs to be investigated. In this study, we investigated the abuse potential of repeated exposure to either 0, 2.5, or 5 mg/kg ketamine administered once weekly for seven weeks. Locomotor activity and conditioned place preference (CPP) were assayed to evaluate behavioral sensitization to the locomotor activating effects of ketamine and its rewarding properties, respectively. Our results show that while neither males nor females developed CPP, males treated with 5 mg/kg and females treated with either 2.5 or 5 mg/kg ketamine behaviorally sensitized. Furthermore, dendritic spine density was increased in the NAc of both males and females administered 5 mg/kg ketamine, an effect specific to the NAc shell (NAcSh) in males but to both the NAc core (NAcC) and NAcSh in females. Additionally, males administered 5 mg/kg ketamine displayed increased protein expression of ΔfosB, calcium calmodulin kinase II alpha (CaMKIIα), and brain-derived neurotrophic factor (BDNF), an effect not observed in females administered either dose of ketamine. However, males and females administered 5 mg/kg ketamine displayed increased protein expression of AMPA receptors (GluA1). Taken together, low-dose ketamine, when administered intermittently, induces behavioral sensitization at a lower dose in females than males, accompanied by an increase in spine density in the NAc and protein expression changes in pathways commonly implicated in addiction.
Show less
Date Issued: 2017-07-15
Identifier: FSU_pmch_28479397, 10.1016/j.neuropharm.2017.05.003, PMC5520991, 28479397, 28479397, S0028-3908(17)30199-5
Format: Citation

Title: A Splice Variant of Centrosomin Converts Mitochondria to Microtubule-Organizing Centers.
Creator: Chen, Jieyan V, Buchwalter, Rebecca A, Kao, Ling-Rong, Megraw, Timothy L
Abstract/Description: Non-centrosomal microtubule organizing centers (MTOCs) direct microtubule (MT) organization to exert diverse cell-type-specific functions. In Drosophila spermatids, the giant mitochondria provide structural platforms for MT reorganization to support elongation of the extremely long sperm. However, the molecular basis for this mitochondrial MTOC and other non-centrosomal MTOCs has not been discerned. Here we report that Drosophila centrosomin (cnn) expresses two major protein variants: the...
Show moreNon-centrosomal microtubule organizing centers (MTOCs) direct microtubule (MT) organization to exert diverse cell-type-specific functions. In Drosophila spermatids, the giant mitochondria provide structural platforms for MT reorganization to support elongation of the extremely long sperm. However, the molecular basis for this mitochondrial MTOC and other non-centrosomal MTOCs has not been discerned. Here we report that Drosophila centrosomin (cnn) expresses two major protein variants: the centrosomal form (CnnC) and a non-centrosomal form in testes (CnnT). CnnC is established as essential for functional centrosomes, the major MTOCs in animal cells. We show that CnnT is expressed exclusively in testes by alternative splicing and localizes to giant mitochondria in spermatids. In cell culture, CnnT targets to the mitochondrial surface, recruits the MT nucleator γ-tubulin ring complex (γ-TuRC), and is sufficient to convert mitochondria to MTOCs independent of core pericentriolar proteins that regulate MT assembly at centrosomes. We mapped two separate domains in CnnT: one that is necessary and sufficient to target it to mitochondria and another that is necessary and sufficient to recruit γ-TuRCs and nucleate MTs. In elongating spermatids, CnnT forms speckles on the giant mitochondria that are required to recruit γ-TuRCs to organize MTs and support spermiogenesis. This molecular characterization of the mitochondrial MTOC defines a minimal molecular requirement for MTOC generation and implicates the potent role of Cnn (or its related) proteins in the direct regulation of MT assembly and organization of non-centrosomal MTOCs.
Show less
Date Issued: 2017-07-10
Identifier: FSU_pmch_28669756, 10.1016/j.cub.2017.05.090, PMC6147254, 28669756, 28669756, S0960-9822(17)30698-X
Format: Citation

Title: An Intact Mcm10 Coiled-coil Interaction Surface Is Important For Origin Melting, Helicase Assembly And The Recruitment Of Pol-alpha To Mcm2-7.
Creator: Perez-Arnaiz, Patricia, Bruck, Irina, Colbert, Max K., Kaplan, Daniel L.
Abstract/Description: Mcm10 is an essential eukaryotic factor required for DNA replication. The replication fork helicase is composed of Cdc45, Mcm2-7 and GINS (CMG). DDK is an S-phase-specific kinase required for replication initiation, and the DNA primase-polymerase in eukaryotes is pol alpha. Mcm10 forms oligomers in vitro, mediated by the coiled-coil domain at the N-terminal region of the protein. We characterized an Mcm10 mutant at the N-terminal Domain (NTD), Mcm10-4A, defective for self-interaction. We...
Show moreMcm10 is an essential eukaryotic factor required for DNA replication. The replication fork helicase is composed of Cdc45, Mcm2-7 and GINS (CMG). DDK is an S-phase-specific kinase required for replication initiation, and the DNA primase-polymerase in eukaryotes is pol alpha. Mcm10 forms oligomers in vitro, mediated by the coiled-coil domain at the N-terminal region of the protein. We characterized an Mcm10 mutant at the N-terminal Domain (NTD), Mcm10-4A, defective for self-interaction. We found that the Mcm10-4A mutant was defective for stimulating DDK phosphorylation of Mcm2, binding to eighty-nucleotide ssDNA, and recruiting pol alpha to Mcm2-7 in vitro. Expression of wild-type levels of mcm10-4A resulted in severe growth and DNA replication defects in budding yeast cells, with diminished DDK phosphorylation of Mcm2. We then expressed the mcm10-4A in mcm5-bob1 mutant cells to bypass the defects mediated by diminished stimulation of DDK phosphorylation of Mcm2. Expression of wild-type levels of mcm10-4A in mcm5-bob1 mutant cells resulted in severe growth and DNA replication defects, along with diminished RPA signal at replication origins. We also detected diminished GINS and pol-alpha recruitment to the Mcm2-7 complex. We conclude that an intact Mcm10 coiled-coil interaction surface is important for originmelting, helicase assembly, and the recruitment of pol alpha to Mcm2-7.
Show less
Date Issued: 2017-07-07
Identifier: FSU_libsubv1_wos_000404879000030, 10.1093/nar/gkx438
Format: Citation

Title: Exercise training reverses age-induced diastolic dysfunction and restores coronary microvascular function.
Creator: Hotta, Kazuki, Chen, Bei, Behnke, Bradley J, Ghosh, Payal, Stabley, John N, Bramy, Jeremy A, Sepulveda, Jaime L, Delp, Michael D, Muller-Delp, Judy M
Abstract/Description: In a rat model of ageing that is free of atherosclerosis or hypertension, E/A, a diagnostic measure of diastolic filling, decreases, and isovolumic relaxation time increases, indicating that both active and passive ventricular relaxation are impaired with advancing age. Resting coronary blood flow and coronary functional hyperaemia are reduced with age, and endothelium-dependent vasodilatation declines with age in coronary resistance arterioles. Exercise training reverses age-induced declines...
Show moreIn a rat model of ageing that is free of atherosclerosis or hypertension, E/A, a diagnostic measure of diastolic filling, decreases, and isovolumic relaxation time increases, indicating that both active and passive ventricular relaxation are impaired with advancing age. Resting coronary blood flow and coronary functional hyperaemia are reduced with age, and endothelium-dependent vasodilatation declines with age in coronary resistance arterioles. Exercise training reverses age-induced declines in diastolic and coronary microvascular function. Thus, microvascular dysfunction and inadequate coronary perfusion are likely mechanisms of diastolic dysfunction in aged rats. Exercise training, initiated at an advanced age, reverses age-related diastolic and microvascular dysfunction; these data suggest that late-life exercise training can be implemented to improve coronary perfusion and diastolic function in the elderly. The risk for diastolic dysfunction increases with advancing age. Regular exercise training ameliorates age-related diastolic dysfunction; however, the underlying mechanisms have not been identified. We investigated whether (1) microvascular dysfunction contributes to the development of age-related diastolic dysfunction, and (2) initiation of late-life exercise training reverses age-related diastolic and microvascular dysfunction. Young and old rats underwent 10 weeks of exercise training or remained as sedentary, cage-controls. Isovolumic relaxation time (IVRT), early diastolic filling (E/A), myocardial performance index (MPI) and aortic stiffness (pulse wave velocity; PWV) were evaluated before and after exercise training or cage confinement. Coronary blood flow and vasodilatory responses of coronary arterioles were evaluated in all groups at the end of training. In aged sedentary rats, compared to young sedentary rats, a 42% increase in IVRT, a 64% decrease in E/A, and increased aortic stiffness (PWV: 6.36 ± 0.47 vs.4.89 ± 0.41, OSED vs. YSED, P < 0.05) was accompanied by impaired coronary blood flow at rest and during exercise. Endothelium-dependent vasodilatation was impaired in coronary arterioles from aged rats (maximal relaxation to bradykinin: 56.4 ± 5.1% vs. 75.3 ± 5.2%, OSED vs. YSED, P < 0.05). After exercise training, IVRT, a measure of active ventricular relaxation, did not differ between old and young rats. In old rats, exercise training reversed the reduction in E/A, reduced aortic stiffness, and eliminated impairment of coronary blood flow responses and endothelium-dependent vasodilatation. Thus, age-related diastolic and microvascular dysfunction are reversed by late-life exercise training. The restorative effect of exercise training on coronary microvascular function may result from improved endothelial function.
Show less
Date Issued: 2017-06-15
Identifier: FSU_pmch_28295341, 10.1113/JP274172, PMC5471361, 28295341, 28295341
Format: Citation

Title: Regulation of BAZ1A and nucleosome positioning in the nucleus accumbens in response to cocaine.
Creator: Sun, HaoSheng, Damez-Werno, Diane M, Scobie, Kimberly N, Shao, Ning-Yi, Dias, Caroline, Rabkin, Jacqui, Wright, Katherine N, Mouzon, Ezekiell, Kabbaj, Mohamed, Neve, Rachael,...
Show moreSun, HaoSheng, Damez-Werno, Diane M, Scobie, Kimberly N, Shao, Ning-Yi, Dias, Caroline, Rabkin, Jacqui, Wright, Katherine N, Mouzon, Ezekiell, Kabbaj, Mohamed, Neve, Rachael, Turecki, Gustavo, Shen, Li, Nestler, Eric J
Show less
Abstract/Description: Chromatin regulation, in particular ATP-dependent chromatin remodelers, have previously been shown to be important in the regulation of reward-related behaviors in animal models of mental illnesses. Here we demonstrate that BAZ1A, an accessory subunit of the ISWI family of chromatin remodeling complexes, is downregulated in the nucleus accumbens (NAc) of mice exposed repeatedly to cocaine and of cocaine-addicted humans. Viral-mediated overexpression of BAZ1A in mouse NAc reduces cocaine...
Show moreChromatin regulation, in particular ATP-dependent chromatin remodelers, have previously been shown to be important in the regulation of reward-related behaviors in animal models of mental illnesses. Here we demonstrate that BAZ1A, an accessory subunit of the ISWI family of chromatin remodeling complexes, is downregulated in the nucleus accumbens (NAc) of mice exposed repeatedly to cocaine and of cocaine-addicted humans. Viral-mediated overexpression of BAZ1A in mouse NAc reduces cocaine reward as assessed by conditioned place preference (CPP), but increases cocaine-induced locomotor activation. Furthermore, we investigate nucleosome repositioning genome-wide by conducting chromatin immunoprecipitation (ChIP)-sequencing for total H3 in NAc of control mice and after repeated cocaine administration, and find extensive nucleosome occupancy and shift changes across the genome in response to cocaine exposure. These findings implicate BAZ1A in molecular and behavioral plasticity to cocaine and offer new insight into the pathophysiology of cocaine addiction.
Show less
Date Issued: 2017-06-14
Identifier: FSU_pmch_28412501, 10.1016/j.neuroscience.2017.04.007, PMC5473651, 28412501, 28412501, S0306-4522(17)30246-4
Format: Citation

Title: OCD candidate gene /EAAT3 impacts basal ganglia-mediated activity and stereotypic behavior.
Creator: Zike, Isaac D, Chohan, Muhammad O, Kopelman, Jared M, Krasnow, Emily N, Flicker, Daniel, Nautiyal, Katherine M, Bubser, Michael, Kellendonk, Christoph, Jones, Carrie K, Stanwood...
Show moreZike, Isaac D, Chohan, Muhammad O, Kopelman, Jared M, Krasnow, Emily N, Flicker, Daniel, Nautiyal, Katherine M, Bubser, Michael, Kellendonk, Christoph, Jones, Carrie K, Stanwood, Gregg, Tanaka, Kenji Fransis, Moore, Holly, Ahmari, Susanne E, Veenstra-VanderWeele, Jeremy
Show less
Abstract/Description: Obsessive-compulsive disorder (OCD) is a chronic, disabling condition with inadequate treatment options that leave most patients with substantial residual symptoms. Structural, neurochemical, and behavioral findings point to a significant role for basal ganglia circuits and for the glutamate system in OCD. Genetic linkage and association studies in OCD point to , which encodes the neuronal glutamate/aspartate/cysteine transporter excitatory amino acid transporter 3 (EAAT3)/excitatory amino...
Show moreObsessive-compulsive disorder (OCD) is a chronic, disabling condition with inadequate treatment options that leave most patients with substantial residual symptoms. Structural, neurochemical, and behavioral findings point to a significant role for basal ganglia circuits and for the glutamate system in OCD. Genetic linkage and association studies in OCD point to , which encodes the neuronal glutamate/aspartate/cysteine transporter excitatory amino acid transporter 3 (EAAT3)/excitatory amino acid transporter 1 (EAAC1). However, no previous studies have investigated EAAT3 in basal ganglia circuits or in relation to OCD-related behavior. Here, we report a model of loss based on an excisable STOP cassette that yields successful ablation of EAAT3 expression and function. Using amphetamine as a probe, we found that EAAT3 loss prevents expected increases in () locomotor activity, () stereotypy, and () immediate early gene induction in the dorsal striatum following amphetamine administration. Further, -STOP mice showed diminished grooming in an SKF-38393 challenge experiment, a pharmacologic model of OCD-like grooming behavior. This reduced grooming is accompanied by reduced dopamine D receptor binding in the dorsal striatum of -STOP mice. -STOP mice also exhibit reduced extracellular dopamine concentrations in the dorsal striatum both at baseline and following amphetamine challenge. Viral-mediated restoration of /EAAT3 expression in the midbrain but not in the striatum results in partial rescue of amphetamine-induced locomotion and stereotypy in -STOP mice, consistent with an impact of EAAT3 loss on presynaptic dopaminergic function. Collectively, these findings indicate that the most consistently associated OCD candidate gene impacts basal ganglia-dependent repetitive behaviors.
Show less
Date Issued: 2017-05-30
Identifier: FSU_pmch_28507136, 10.1073/pnas.1701736114, PMC5465902, 28507136, 28507136, 1701736114
Format: Citation

Title: An intact Mcm10 coiled-coil interaction surface is important for origin melting, helicase assembly and the recruitment of Pol-α to Mcm2-7.
Creator: Perez-Arnaiz, Patricia, Bruck, Irina, Colbert, Max K, Kaplan, Daniel L
Abstract/Description: Mcm10 is an essential eukaryotic factor required for DNA replication. The replication fork helicase is composed of Cdc45, Mcm2-7 and GINS (CMG). DDK is an S-phase-specific kinase required for replication initiation, and the DNA primase-polymerase in eukaryotes is pol α. Mcm10 forms oligomers in vitro, mediated by the coiled-coil domain at the N-terminal region of the protein. We characterized an Mcm10 mutant at the N-terminal Domain (NTD), Mcm10-4A, defective for self-interaction. We found...
Show moreMcm10 is an essential eukaryotic factor required for DNA replication. The replication fork helicase is composed of Cdc45, Mcm2-7 and GINS (CMG). DDK is an S-phase-specific kinase required for replication initiation, and the DNA primase-polymerase in eukaryotes is pol α. Mcm10 forms oligomers in vitro, mediated by the coiled-coil domain at the N-terminal region of the protein. We characterized an Mcm10 mutant at the N-terminal Domain (NTD), Mcm10-4A, defective for self-interaction. We found that the Mcm10-4A mutant was defective for stimulating DDK phosphorylation of Mcm2, binding to eighty-nucleotide ssDNA, and recruiting pol α to Mcm2-7 in vitro. Expression of wild-type levels of mcm10-4A resulted in severe growth and DNA replication defects in budding yeast cells, with diminished DDK phosphorylation of Mcm2. We then expressed the mcm10-4A in mcm5-bob1 mutant cells to bypass the defects mediated by diminished stimulation of DDK phosphorylation of Mcm2. Expression of wild-type levels of mcm10-4A in mcm5-bob1 mutant cells resulted in severe growth and DNA replication defects, along with diminished RPA signal at replication origins. We also detected diminished GINS and pol-α recruitment to the Mcm2-7 complex. We conclude that an intact Mcm10 coiled-coil interaction surface is important for origin melting, helicase assembly, and the recruitment of pol α to Mcm2-7.
Show less
Date Issued: 2017-05-16
Identifier: FSU_pmch_28510759, 10.1093/nar/gkx438, PMC5499591, 28510759, 28510759, 3828234
Format: Citation

Title: Dpb11 May Function With Rpa And Dna To Initiate Dna Replication.
Creator: Bruck, Irina, Dhingra, Nalini, Martinez, Matthew P., Kaplan, Daniel L.
Abstract/Description: Dpb11 is required for the initiation of DNA replication in budding yeast. We found that Dpb11 binds tightly to single-stranded DNA (ssDNA) or branched DNA structures, while its human homolog, TopBP1, binds tightly to branched-DNA structures. We also found that Dpb11 binds stably to CDK-phosphorylated RPA, the eukaryotic ssDNA binding protein, in the presence of branched DNA. A Dpb11 mutant specifically defective for DNA binding did not exhibit tight binding to RPA in the presence of DNA,...
Show moreDpb11 is required for the initiation of DNA replication in budding yeast. We found that Dpb11 binds tightly to single-stranded DNA (ssDNA) or branched DNA structures, while its human homolog, TopBP1, binds tightly to branched-DNA structures. We also found that Dpb11 binds stably to CDK-phosphorylated RPA, the eukaryotic ssDNA binding protein, in the presence of branched DNA. A Dpb11 mutant specifically defective for DNA binding did not exhibit tight binding to RPA in the presence of DNA, suggesting that Dpb11-interaction with DNA may promote the recruitment of RPA to melted DNA. We then characterized a mutant of Dpb11 that is specifically defective in DNA binding in budding yeast cells. Expression of dpb11-m1,2,3,5,Delta C results in a substantial decrease in RPA recruitment to origins, suggesting that Dpb11 interaction with DNA may be required for RPA recruitment to origins. Expression of dpb11-m1,2,3,5,Delta C also results in diminished GINS interaction with Mcm2-7 during S phase, while Cdc45 interaction with Mcm2-7 is like wild-type. The reduced GINS interaction with Mcm2-7 may be an indirect consequence of diminished origin melting. We propose that the tight interaction between Dpb11, CDK-phosphorylated RPA, and branched-DNA may be required for the essential function of stabilizing melted origin DNA in vivo. We also propose an alternative model, wherein Dpb11-DNA interaction is required for some other function in DNA replication initiation, such as helicase activation.
Show less
Date Issued: 2017-05-03
Identifier: FSU_libsubv1_wos_000400647000095, 10.1371/journal.pone.0177147
Format: Citation

Title: Dpb11 may function with RPA and DNA to initiate DNA replication.
Creator: Bruck, Irina, Dhingra, Nalini, Martinez, Matthew P, Kaplan, Daniel L
Abstract/Description: Dpb11 is required for the initiation of DNA replication in budding yeast. We found that Dpb11 binds tightly to single-stranded DNA (ssDNA) or branched DNA structures, while its human homolog, TopBP1, binds tightly to branched-DNA structures. We also found that Dpb11 binds stably to CDK-phosphorylated RPA, the eukaryotic ssDNA binding protein, in the presence of branched DNA. A Dpb11 mutant specifically defective for DNA binding did not exhibit tight binding to RPA in the presence of DNA,...
Show moreDpb11 is required for the initiation of DNA replication in budding yeast. We found that Dpb11 binds tightly to single-stranded DNA (ssDNA) or branched DNA structures, while its human homolog, TopBP1, binds tightly to branched-DNA structures. We also found that Dpb11 binds stably to CDK-phosphorylated RPA, the eukaryotic ssDNA binding protein, in the presence of branched DNA. A Dpb11 mutant specifically defective for DNA binding did not exhibit tight binding to RPA in the presence of DNA, suggesting that Dpb11-interaction with DNA may promote the recruitment of RPA to melted DNA. We then characterized a mutant of Dpb11 that is specifically defective in DNA binding in budding yeast cells. Expression of dpb11-m1,2,3,5,ΔC results in a substantial decrease in RPA recruitment to origins, suggesting that Dpb11 interaction with DNA may be required for RPA recruitment to origins. Expression of dpb11-m1,2,3,5,ΔC also results in diminished GINS interaction with Mcm2-7 during S phase, while Cdc45 interaction with Mcm2-7 is like wild-type. The reduced GINS interaction with Mcm2-7 may be an indirect consequence of diminished origin melting. We propose that the tight interaction between Dpb11, CDK-phosphorylated RPA, and branched-DNA may be required for the essential function of stabilizing melted origin DNA in vivo. We also propose an alternative model, wherein Dpb11-DNA interaction is required for some other function in DNA replication initiation, such as helicase activation.
Show less
Date Issued: 2017-05-03
Identifier: FSU_pmch_28467467, 10.1371/journal.pone.0177147, PMC5415106, 28467467, 28467467, PONE-D-17-03239
Format: Citation

Title: Myosin Rod Hypophosphorylation and CB Kinetics in Papillary Muscles from a TnC-A8V KI Mouse Model.
Creator: Kawai, Masataka, Johnston, Jamie R, Karam, Tarek, Wang, Li, Singh, Rakesh K, Pinto, Jose R
Abstract/Description: The cardiac troponin C (TnC)-A8V mutation is associated with hypertrophic and restrictive cardiomyopathy (HCM and RCM) in human and mice. The residue affected lies in the N-helix, a region known to affect Ca-binding affinity to the N-terminal domain. Here we report on the functional effects of this mutation in skinned papillary muscle fibers from homozygous knock-in TnC-A8V mice. Muscle fibers from left ventricle were activated at 25°C under the ionic conditions of working cardiomyocytes. The...
Show moreThe cardiac troponin C (TnC)-A8V mutation is associated with hypertrophic and restrictive cardiomyopathy (HCM and RCM) in human and mice. The residue affected lies in the N-helix, a region known to affect Ca-binding affinity to the N-terminal domain. Here we report on the functional effects of this mutation in skinned papillary muscle fibers from homozygous knock-in TnC-A8V mice. Muscle fibers from left ventricle were activated at 25°C under the ionic conditions of working cardiomyocytes. The pCa-tension relationship showed a 3× increase in Ca-sensitivity and a decrease (0.8×) in cooperativity (n) in mutant fibers. The elementary steps of the cross-bridge (CB) cycle were investigated by sinusoidal analysis. The ATP study revealed that there is no significant change in the affinity of ATP (K) for the myosin head. In TnC-A8V mutant fibers, the CB detachment rate (k) and its equilibrium constant (K) increased (1.5×). The phosphate study revealed that rate constant of the force-generation step (k) decreased (0.5×), reversal step (k) increased (2×), and the phosphate-release step (1/K) increased (2×). Pro-Q Diamond staining of the skinned fibers samples revealed no significant changes in total phosphorylation of multiple sarcomeric proteins. Further investigation using liquid chromatography-tandem mass spectrometry revealed hypophosphorylation of the rod domain of myosin heavy chain in TnC-A8V mutant fibers compared to wild-type. Immunoblotting confirmed the results observed in the mass spectrometry analysis. The results suggest perturbed CB kinetics-possibly caused by changes in the α-myosin heavy chain phosphorylation profile-as a novel mechanism, to our knowledge, by which a mutation in TnC can have rippling effects in the myofilament and contribute to the pathogenesis of HCM/RCM.
Show less
Date Issued: 2017-04-25
Identifier: FSU_pmch_28445763, 10.1016/j.bpj.2017.02.045, PMC5406373, 28445763, 28445763, S0006-3495(17)30295-3
Format: Citation

Title: Genetic Influences on Pharmacological Interventions in Psoriasis.
Creator: Ahmed, Hana, Yusuf, Nabiha
Abstract/Description: Psoriasis is a common chronic inflammatory disease that affects 2% of the population. Therapeutic intervention for psoriasis mainly targets inflammatory cascade through the use of topical agents, phototherapy, systemic agents and the newer biologic agents. The efficacy of many treatments used in psoriasis varies from patient to patient, and some of this variance in response can presumably be attributed to genetic differences. While current research findings are still limited, the clinical...
Show morePsoriasis is a common chronic inflammatory disease that affects 2% of the population. Therapeutic intervention for psoriasis mainly targets inflammatory cascade through the use of topical agents, phototherapy, systemic agents and the newer biologic agents. The efficacy of many treatments used in psoriasis varies from patient to patient, and some of this variance in response can presumably be attributed to genetic differences. While current research findings are still limited, the clinical utilization of pharmacogenetics allows for tailored treatment plans that have the potential for better response amongst patients as well as conserving expenditures and healthcare resources. In this review, we hope to focus and summarize the conclusions and findings of studies done on the topic of pharmacogenetics in the treatment of psoriasis.
Show less
Date Issued: 2017-04-24
Identifier: FSU_libsubv1_scholarship_submission_1516305863_e8df6723, 10.4172/2155-9554.1000392
Format: Citation

Title: Hypertrophic Cardiomyopathy Cardiac Troponin C Mutations Differentially Affect Slow Skeletal And Cardiac Muscle Regulation.
Creator: Veltri, Tiago, Landim-Vieira, Maicon, Parvatiyar, Michelle S., Gonzalez-Martinez, David, Jones, Karissa M. Dieseldorff, Michell, Clara A., Dweck, David, Landstrom, Andrew P.,...
Show moreVeltri, Tiago, Landim-Vieira, Maicon, Parvatiyar, Michelle S., Gonzalez-Martinez, David, Jones, Karissa M. Dieseldorff, Michell, Clara A., Dweck, David, Landstrom, Andrew P., Chase, P. Bryant, Pinto, Jose R.
Show less
Abstract/Description: Mutations in TNNC1-the gene encoding cardiac troponin C (cTnC)-that have been associated with hypertrophic cardiomyopathy (HCM) and cardiac dysfunction may also affect Ca2+-regulation and function of slow skeletal muscle since the same gene is expressed in both cardiac and slow skeletal muscle. Therefore, we reconstituted rabbit soleus fibers and bovine masseter myofibrils with mutant cTnCs (A8V, C84Y, E134D, and D145E) associated with HCM to investigate their effects on contractile force and...
Show moreMutations in TNNC1-the gene encoding cardiac troponin C (cTnC)-that have been associated with hypertrophic cardiomyopathy (HCM) and cardiac dysfunction may also affect Ca2+-regulation and function of slow skeletal muscle since the same gene is expressed in both cardiac and slow skeletal muscle. Therefore, we reconstituted rabbit soleus fibers and bovine masseter myofibrils with mutant cTnCs (A8V, C84Y, E134D, and D145E) associated with HCM to investigate their effects on contractile force and ATPase rates, respectively. Previously, we showed that these HCM cTnC mutants, except for E134D, increased the Ca2+ sensitivity of force development in cardiac preparations. In the current study, an increase in Ca2+ sensitivity of isometric force was only observed for the C84Y mutant when reconstituted in soleus fibers. Incorporation of cTnC C84Y in bovine masseter myofibrils reduced the ATPase activity at saturating [Ca2+], whereas, incorporation of cTnC D145E increased the ATPase activity at inhibiting and saturating [Ca2+]. We also tested whether reconstitution of cardiac fibers with troponin complexes containing the cTnC mutants and slow skeletal troponin I (ssTnI) could emulate the slow skeletal functional phenotype. Reconstitution of cardiac fibers with troponin complexes containing ssTnI attenuated the Ca2+ sensitization of isometric force when cTnC A8V and D145E were present; however, it was enhanced for C84Y. In summary, although the A8V and D145E mutants are present in both muscle types, their functional phenotype is more prominent in cardiac muscle than in slow skeletal muscle, which has implications for the protein-protein interactions within the troponin complex. The C84Y mutant warrants further investigation since it drastically alters the properties of both muscle types and may account for the earlier clinical onset in the proband.
Show less
Date Issued: 2017-04-20
Identifier: FSU_libsubv1_wos_000402869900001, 10.3389/fphys.2017.00221, PMC5397416
Format: Citation

Title: Distinct Neural Properties in the Low-Frequency Region of the Chicken Cochlear Nucleus Magnocellularis.
Creator: Wang, Xiaoyu, Hong, Hui, Brown, David H, Sanchez, Jason Tait, Wang, Yuan
Abstract/Description: Topography in the avian cochlear nucleus magnocellularis (NM) is represented as gradually increasing characteristic frequency (CF) along the caudolateral-to-rostromedial axis. In this study, we characterized the organization and cell biophysics of the caudolateral NM (NMc) in chickens (Gallus gallus). Examination of cellular and dendritic architecture first revealed that NMc contains small neurons and extensive dendritic processes, in contrast to adendritic, large neurons located more...
Show moreTopography in the avian cochlear nucleus magnocellularis (NM) is represented as gradually increasing characteristic frequency (CF) along the caudolateral-to-rostromedial axis. In this study, we characterized the organization and cell biophysics of the caudolateral NM (NMc) in chickens (Gallus gallus). Examination of cellular and dendritic architecture first revealed that NMc contains small neurons and extensive dendritic processes, in contrast to adendritic, large neurons located more rostromedially. Individual dye-filling study further demonstrated that NMc is divided into two subregions, with NMc2 neurons having larger and more complex dendritic fields than NMc1. Axonal tract tracing studies confirmed that NMc1 and NMc2 neurons receive afferent inputs from the auditory nerve and the superior olivary nucleus, similar to the adendritic NM. However, the auditory axons synapse with NMc neurons via small bouton-like terminals, unlike the large end bulb synapses on adendritic NM neurons. Immunocytochemistry demonstrated that most NMc2 neurons express cholecystokinin but not calretinin, distinct from NMc1 and adendritic NM neurons that are cholecystokinin negative and mostly calretinin positive. Finally, whole-cell current clamp recordings revealed that NMc neurons require significantly lower threshold current for action potential generation than adendritic NM neurons. Moreover, in contrast to adendritic NM neurons that generate a single-onset action potential, NMc neurons generate multiple action potentials to suprathreshold sustained depolarization. Taken together, our data indicate that NMc contains multiple neuron types that are structurally, connectively, molecularly, and physiologically different from traditionally defined NM neurons, emphasizing specialized neural properties for processing low-frequency sounds.
Show less
Date Issued: 2017-04-11
Identifier: FSU_pmch_28413822, 10.1523/ENEURO.0016-17.2017, PMC5388668, 28413822, 28413822, eN-NWR-0016-17
Format: Citation

Title: Distinct neural properties in the low frequency region of the chicken cochlear nucleus magnocellularis.
Creator: Wang, Xiaoyu, Hong, Hui, Brown, David H., Sanchez, Jason T., Wang, Yuan
Abstract/Description: Topography in the avian cochlear nucleus magnocellularis (NM) is represented as gradually increasing characteristic frequency (CF) along the caudolateral to rostromedial axis. In this study, we characterized the organization and cell biophysics of the caudolateral NM (NMc) in chickens (Gallus gallus domesticus). Examination of cellular and dendritic architecture first revealed that NMc contains small neurons and extensive dendritic processes, in contrast to adendritic, large neurons located...
Show moreTopography in the avian cochlear nucleus magnocellularis (NM) is represented as gradually increasing characteristic frequency (CF) along the caudolateral to rostromedial axis. In this study, we characterized the organization and cell biophysics of the caudolateral NM (NMc) in chickens (Gallus gallus domesticus). Examination of cellular and dendritic architecture first revealed that NMc contains small neurons and extensive dendritic processes, in contrast to adendritic, large neurons located more rostromedially. Individual dye-filling study further demonstrated that NMc is divided into two subregions, with NMc2 neurons having larger and more complex dendritic fields than NMc1. Axonal tract tracing studies confirmed that NMc1 and NMc2 neurons receive afferent inputs from the auditory nerve and the superior olivary nucleus, similar to the adendritic NM. However, the auditory axons synapse with NMc neurons via small bouton-like terminals, unlike the large end-bulb synapses on adendritic NM neurons. Immunocytochemistry demonstrated that most NMc2 neurons express cholecystokinin but not calretinin, distinct from NMc1 and adendritic NM neurons that are cholecystokinin-negative and mostly calretinin-positive. Finally, whole-cell current clamp recordings revealed that NMc neurons require significantly lower threshold current for action potential generation than adendritic NM neurons. Moreover, in contrast to adendritic NM neurons that generate a single onset action potential, NMc neurons generate multiple action potentials to suprathreshold sustained depolarization. Taken together, our data indicate that NMc contains multiple neuron types that are structurally, connectively, molecularly, and physiologically different from traditionally defined NM neurons, emphasizing specialized neural properties for processing low frequency sounds.
Show less
Date Issued: 2017-04-11
Identifier: FSU_libsubv1_scholarship_submission_1511841863_674f6e29, 10.1523/ENEURO.0016-17.2017
Format: Citation

Title: Amide Hydrogens Reveal A Temperature-dependent Structural Transition That Enhances Site-ii Ca2+ -binding Affinity In A C-domain Mutant Of Cardiac Troponin C.
Creator: Veltri, Tiago, de Oliveira, Guilherme A. P., Bienkiewicz, Ewa A., Palhano, Fernando L., Marques, Mayra de A., Moraes, Adolfo H., Silva, Jerson L., Sorenson, Martha M., Pinto,...
Show moreVeltri, Tiago, de Oliveira, Guilherme A. P., Bienkiewicz, Ewa A., Palhano, Fernando L., Marques, Mayra de A., Moraes, Adolfo H., Silva, Jerson L., Sorenson, Martha M., Pinto, Jose R.
Show less
Abstract/Description: The hypertrophic cardiomyopathy-associated mutant D145E, in cardiac troponin C (cTnC) C-domain, causes generalised instability at multiple sites in the isolated protein. As a result, structure and function of the mutant are more susceptible to higher temperatures. Above 25 degrees C there are large, progressive increases in N-domain Ca2+-binding affinity for D145E but only small changes for the wild-type protein. NMR-derived backbone amide temperature coefficients for many residues show a...
Show moreThe hypertrophic cardiomyopathy-associated mutant D145E, in cardiac troponin C (cTnC) C-domain, causes generalised instability at multiple sites in the isolated protein. As a result, structure and function of the mutant are more susceptible to higher temperatures. Above 25 degrees C there are large, progressive increases in N-domain Ca2+-binding affinity for D145E but only small changes for the wild-type protein. NMR-derived backbone amide temperature coefficients for many residues show a sharp transition above 30-40 degrees C, indicating a temperature-dependent conformational change that is most prominent around the mutated EF-hand IV, as well as throughout the C-domain. Smaller, isolated changes occur in the N-domain. Cardiac skinned fibres reconstituted with D145E are more sensitive to Ca2+ than fibres reconstituted with wild-type, and this defect is amplified near body-temperature. We speculate that the D145E mutation destabilises the native conformation of EF-hand IV, leading to a transient unfolding and dissociation of helix H that becomes more prominent at higher temperatures. This creates exposed hydrophobic surfaces that may be capable of binding unnaturally to a variety of targets, possibly including the N-domain of cTnC when it is in its open Ca2+-saturated state. This would constitute a potential route for propagating signals from one end of TnC to the other.
Show less
Date Issued: 2017-04-06
Identifier: FSU_libsubv1_wos_000398545900010, 10.1038/s41598-017-00777-6
Format: Citation

Title: Amide hydrogens reveal a temperature-dependent structural transition that enhances site-II Ca(2+)-binding affinity in a C-domain mutant of cardiac troponin C.
Creator: Veltri, Tiago, de Oliveira, Guilherme A P, Bienkiewicz, Ewa A, Palhano, Fernando L, Marques, Mayra de A, Moraes, Adolfo H, Silva, Jerson L, Sorenson, Martha M, Pinto, Jose R
Abstract/Description: The hypertrophic cardiomyopathy-associated mutant D145E, in cardiac troponin C (cTnC) C-domain, causes generalised instability at multiple sites in the isolated protein. As a result, structure and function of the mutant are more susceptible to higher temperatures. Above 25 °C there are large, progressive increases in N-domain Ca(2+)-binding affinity for D145E but only small changes for the wild-type protein. NMR-derived backbone amide temperature coefficients for many residues show a sharp...
Show moreThe hypertrophic cardiomyopathy-associated mutant D145E, in cardiac troponin C (cTnC) C-domain, causes generalised instability at multiple sites in the isolated protein. As a result, structure and function of the mutant are more susceptible to higher temperatures. Above 25 °C there are large, progressive increases in N-domain Ca(2+)-binding affinity for D145E but only small changes for the wild-type protein. NMR-derived backbone amide temperature coefficients for many residues show a sharp transition above 30-40 °C, indicating a temperature-dependent conformational change that is most prominent around the mutated EF-hand IV, as well as throughout the C-domain. Smaller, isolated changes occur in the N-domain. Cardiac skinned fibres reconstituted with D145E are more sensitive to Ca(2+) than fibres reconstituted with wild-type, and this defect is amplified near body-temperature. We speculate that the D145E mutation destabilises the native conformation of EF-hand IV, leading to a transient unfolding and dissociation of helix H that becomes more prominent at higher temperatures. This creates exposed hydrophobic surfaces that may be capable of binding unnaturally to a variety of targets, possibly including the N-domain of cTnC when it is in its open Ca(2+)-saturated state. This would constitute a potential route for propagating signals from one end of TnC to the other.
Show less
Date Issued: 2017-04-06
Identifier: FSU_pmch_28386062, 10.1038/s41598-017-00777-6, PMC5429600, 28386062, 28386062, 10.1038/s41598-017-00777-6
Format: Citation

Title: Eukaryotic Replicative Helicase Subunit Interaction with DNA and Its Role in DNA Replication.
Creator: Martinez, Matthew P, Wacker, Amanda L, Bruck, Irina, Kaplan, Daniel L
Abstract/Description: The replicative helicase unwinds parental double-stranded DNA at a replication fork to provide single-stranded DNA templates for the replicative polymerases. In eukaryotes, the replicative helicase is composed of the Cdc45 protein, the heterohexameric ring-shaped Mcm2-7 complex, and the tetrameric GINS complex (CMG). The CMG proteins bind directly to DNA, as demonstrated by experiments with purified proteins. The mechanism and function of these DNA-protein interactions are presently being...
Show moreThe replicative helicase unwinds parental double-stranded DNA at a replication fork to provide single-stranded DNA templates for the replicative polymerases. In eukaryotes, the replicative helicase is composed of the Cdc45 protein, the heterohexameric ring-shaped Mcm2-7 complex, and the tetrameric GINS complex (CMG). The CMG proteins bind directly to DNA, as demonstrated by experiments with purified proteins. The mechanism and function of these DNA-protein interactions are presently being investigated, and a number of important discoveries relating to how the helicase proteins interact with DNA have been reported recently. While some of the protein-DNA interactions directly relate to the unwinding function of the enzyme complex, other protein-DNA interactions may be important for minichromosome maintenance (MCM) loading, origin melting or replication stress. This review describes our current understanding of how the eukaryotic replicative helicase subunits interact with DNA structures in vitro, and proposed models for the in vivo functions of replicative helicase-DNA interactions are also described.
Show less
Date Issued: 2017-04-06
Identifier: FSU_pmch_28383499, 10.3390/genes8040117, PMC5406864, 28383499, 28383499, genes8040117
Format: Citation

Title: Eukaryotic Replicative Helicase Subunit Interaction With Dna And Its Role In Dna Replication.
Creator: Martinez, Matthew P., Wacker, Amanda L., Bruck, Irina, Kaplan, Daniel L.
Abstract/Description: The replicative helicase unwinds parental double-stranded DNA at a replication fork to provide single-stranded DNA templates for the replicative polymerases. In eukaryotes, the replicative helicase is composed of the Cdc45 protein, the heterohexameric ring-shaped Mcm2-7 complex, and the tetrameric GINS complex (CMG). The CMG proteins bind directly to DNA, as demonstrated by experiments with purified proteins. The mechanism and function of these DNA-protein interactions are presently being...
Show moreThe replicative helicase unwinds parental double-stranded DNA at a replication fork to provide single-stranded DNA templates for the replicative polymerases. In eukaryotes, the replicative helicase is composed of the Cdc45 protein, the heterohexameric ring-shaped Mcm2-7 complex, and the tetrameric GINS complex (CMG). The CMG proteins bind directly to DNA, as demonstrated by experiments with purified proteins. The mechanism and function of these DNA-protein interactions are presently being investigated, and a number of important discoveries relating to how the helicase proteins interact with DNA have been reported recently. While some of the protein-DNA interactions directly relate to the unwinding function of the enzyme complex, other protein-DNA interactions may be important for minichromosome maintenance (MCM) loading, origin melting or replication stress. This review describes our current understanding of how the eukaryotic replicative helicase subunits interact with DNA structures in vitro, and proposed models for the in vivo functions of replicative helicase-DNA interactions are also described.
Show less
Date Issued: 2017-04
Identifier: FSU_libsubv1_wos_000404391700012, 10.3390/genes8040117
Format: Citation

Title: Will You Still Need Me (ca2+, Tnt, And Dhpr), Will You Still Cleave Me (calpain), When I'm 64?.
Creator: Pinto, Jose Renato, Muller-Delp, Judy, Chase, P. Bryant
Date Issued: 2017-04
Identifier: FSU_libsubv1_wos_000395379500001, 10.1111/acel.12560
Format: Citation

Title: Will you still need me (Ca(2+) , TnT, and DHPR), will you still cleave me (calpain), when I'm 64?.
Creator: Pinto, José Renato, Muller-Delp, Judy, Chase, P Bryant
Date Issued: 2017-04-01
Identifier: FSU_pmch_28008709, 10.1111/acel.12560, PMC5334566, 28008709, 28008709
Format: Citation

Title: Integrative analysis of sex differences in the rapid antidepressant effects of ketamine in preclinical models for individualized clinical outcomes.
Creator: Saland, Samantha K, Duclot, Florian, Kabbaj, Mohamed
Abstract/Description: In major depressive disorder, women exhibit higher lifetime prevalence and different antidepressant response rates than men, which illustrates the importance of examining individual differences in the pathophysiology of depression and therapeutic response. In recent years, the consideration of sex in related preclinical research has thus gained interest-particularly in light of novel evidence for rapid-acting antidepressants. Notably, the literature recently revealed a higher sensitivity of...
Show moreIn major depressive disorder, women exhibit higher lifetime prevalence and different antidepressant response rates than men, which illustrates the importance of examining individual differences in the pathophysiology of depression and therapeutic response. In recent years, the consideration of sex in related preclinical research has thus gained interest-particularly in light of novel evidence for rapid-acting antidepressants. Notably, the literature recently revealed a higher sensitivity of females to the antidepressant effects of the N-methyl-D-aspartate receptor antagonist ketamine, in both baseline and preclinical conditions. Combined with its fast-acting and relatively sustained properties, this evidence highlights ketamine as a particularly interesting therapeutic alternative for this sensitive population, and supports the value in considering sex as a critical factor for improved individualized therapeutic strategies.
Show less
Date Issued: 2017-04-01
Identifier: FSU_pmch_28584860, 10.1016/j.cobeha.2016.11.002, PMC5456295, 28584860, 28584860
Format: Citation

Title: La-related protein 6 controls ciliated cell differentiation.
Creator: Manojlovic, Zarko, Earwood, Ryan, Kato, Akiko, Perez, Diana, Cabrera, Oscar A, Didier, Ruth, Megraw, Timothy L, Stefanovic, Branko, Kato, Yoichi
Abstract/Description: La-related protein 6 (LARP6) is an evolutionally conserved RNA-binding protein. Vertebrate LARP6 binds the 5' stem-loop found in mRNAs encoding type I collagen to regulate their translation, but other target mRNAs and additional functions for LARP6 are unknown. The aim of this study was to elucidate an additional function of LARP6 and to evaluate the importance of its function during development. To uncover the role of LARP6 in development, we utilized Morpholino Oligos to deplete LARP6...
Show moreLa-related protein 6 (LARP6) is an evolutionally conserved RNA-binding protein. Vertebrate LARP6 binds the 5' stem-loop found in mRNAs encoding type I collagen to regulate their translation, but other target mRNAs and additional functions for LARP6 are unknown. The aim of this study was to elucidate an additional function of LARP6 and to evaluate the importance of its function during development. To uncover the role of LARP6 in development, we utilized Morpholino Oligos to deplete LARP6 protein in Xenopus embryos. Then, embryonic phenotypes and ciliary structures of LAPR6 morphants were examined. To identify the molecular mechanism underlying ciliogenesis regulated by LARP6, we tested the expression level of cilia-related genes, which play important roles in ciliogenesis, by RT-PCR or whole mount in situ hybridization (WISH). We knocked down LARP6 in Xenopus embryos and found neural tube closure defects. LARP6 mutant, which compromises the collagen synthesis, could rescue these defects. Neural tube closure defects are coincident with lack of cilia, antenna-like cellular organelles with motility- or sensory-related functions, in the neural tube. The absence of cilia at the epidermis was also observed in LARP6 morphants, and this defect was due to the absence of basal bodies which are formed from centrioles and required for ciliary assembly. In the process of multi-ciliated cell (MCC) differentiation, mcidas, which activates the transcription of genes required for centriole formation during ciliogenesis, could partially restore MCCs in LARP6 morphants. In addition, LARP6 likely controls the expression of mcidas in a Notch-independent manner. La-related protein 6 is involved in ciliated cell differentiation during development by controlling the expression of cilia-related genes including mcidas. This LARP6 function involves a mechanism that is distinct from its established role in binding to collagen mRNAs and regulating their translation.
Show less
Date Issued: 2017-03-23
Identifier: FSU_pmch_28344782, 10.1186/s13630-017-0047-7, PMC5364628, 28344782, 28344782, 47
Format: Citation

Title: Sex Differences In The Molecular Signature Of The Developing Mouse Hippocampus.
Creator: Bundy, Joseph L., Vied, Cynthia, Nowakowski, Richard S.
Abstract/Description: Background: A variety of neurological disorders, including Alzheimer's disease, Parkinson's disease, major depressive disorder, dyslexia and autism, are differentially prevalent between females and males. To better understand the possible molecular basis for the sex-biased nature of neurological disorders, we used a developmental series of female and male mice at 1, 2, and 4 months of age to assess both mRNA and protein in the hippocampus with RNA-sequencing and mass-spectrometry,...
Show moreBackground: A variety of neurological disorders, including Alzheimer's disease, Parkinson's disease, major depressive disorder, dyslexia and autism, are differentially prevalent between females and males. To better understand the possible molecular basis for the sex-biased nature of neurological disorders, we used a developmental series of female and male mice at 1, 2, and 4 months of age to assess both mRNA and protein in the hippocampus with RNA-sequencing and mass-spectrometry, respectively. Results: The transcriptomic analysis identifies 2699 genes that are differentially expressed between animals of different ages. The bulk of these differentially expressed genes are changed in both sexes at one or more ages, but a total of 198 transcripts are differentially expressed between females and males at one or more ages. The number of transcripts that are differentially expressed between females and males is greater in adult animals than in younger animals. Additionally, we identify 69 transcripts that show complex and sex-specific patterns of temporal regulation through postnatal development, 8 of which are heat-shock proteins. We also find a modest correlation between levels of mRNA and protein in the mouse hippocampus (Rho = 0.53). Conclusion: This study adds to the substantial body of evidence for transcriptomic regulation in the hippocampus during postnatal development. Additionally, this analysis reveals sex differences in the transcriptome of the developing mouse hippocampus, and further clarifies the need to include both female and male mice in longitudinal studies involving molecular changes in the hippocampus.
Show less
Date Issued: 2017-03-16
Identifier: FSU_libsubv1_wos_000396759300004, 10.1186/s12864-017-3608-7
Format: Citation

Title: Sex differences in the molecular signature of the developing mouse hippocampus.
Creator: Bundy, Joseph L, Vied, Cynthia, Nowakowski, Richard S
Abstract/Description: A variety of neurological disorders, including Alzheimer's disease, Parkinson's disease, major depressive disorder, dyslexia and autism, are differentially prevalent between females and males. To better understand the possible molecular basis for the sex-biased nature of neurological disorders, we used a developmental series of female and male mice at 1, 2, and 4 months of age to assess both mRNA and protein in the hippocampus with RNA-sequencing and mass-spectrometry, respectively. The...
Show moreA variety of neurological disorders, including Alzheimer's disease, Parkinson's disease, major depressive disorder, dyslexia and autism, are differentially prevalent between females and males. To better understand the possible molecular basis for the sex-biased nature of neurological disorders, we used a developmental series of female and male mice at 1, 2, and 4 months of age to assess both mRNA and protein in the hippocampus with RNA-sequencing and mass-spectrometry, respectively. The transcriptomic analysis identifies 2699 genes that are differentially expressed between animals of different ages. The bulk of these differentially expressed genes are changed in both sexes at one or more ages, but a total of 198 transcripts are differentially expressed between females and males at one or more ages. The number of transcripts that are differentially expressed between females and males is greater in adult animals than in younger animals. Additionally, we identify 69 transcripts that show complex and sex-specific patterns of temporal regulation through postnatal development, 8 of which are heat-shock proteins. We also find a modest correlation between levels of mRNA and protein in the mouse hippocampus (Rho = 0.53). This study adds to the substantial body of evidence for transcriptomic regulation in the hippocampus during postnatal development. Additionally, this analysis reveals sex differences in the transcriptome of the developing mouse hippocampus, and further clarifies the need to include both female and male mice in longitudinal studies involving molecular changes in the hippocampus.
Show less
Date Issued: 2017-03-16
Identifier: FSU_pmch_28302071, 10.1186/s12864-017-3608-7, PMC5356301, 28302071, 28302071, 10.1186/s12864-017-3608-7
Format: Citation

Title: The Role Of Early Growth Response 1 (egr1) In Brain Plasticity And Neuropsychiatric Disorders.
Creator: Duclot, Florian, Kabbaj, Mohamed
Abstract/Description: It is now clearly established that complex interactions between genes and environment are involved in multiple aspects of neuropsychiatric disorders, from determining an individual's vulnerability to onset, to influencing its response to therapeutic intervention. In this perspective, it appears crucial to better understand how the organism reacts to environmental stimuli and provide a coordinated and adapted response. In the central nervous system, neuronal plasticity and neurotransmission...
Show moreIt is now clearly established that complex interactions between genes and environment are involved in multiple aspects of neuropsychiatric disorders, from determining an individual's vulnerability to onset, to influencing its response to therapeutic intervention. In this perspective, it appears crucial to better understand how the organism reacts to environmental stimuli and provide a coordinated and adapted response. In the central nervous system, neuronal plasticity and neurotransmission are among the major processes integrating such complex interactions between genes and environmental stimuli. In particular, immediate early genes (IEGs) are critical components of these interactions as they provide the molecular framework for a rapid and dynamic response to neuronal activity while opening the possibility for a lasting and sustained adaptation through regulation of the expression of a wide range of genes. As a result, IEGs have been tightly associated with neuronal activity as well as a variety of higher order processes within the central nervous system such as learning, memory and sensitivity to reward. The immediate early gene and transcription factor early growth response 1 (EGR1) has thus been revealed as a major mediator and regulator of synaptic plasticity and neuronal activity in both physiological and pathological conditions. In this review article, we will focus on the role of EGR1 in the central nervous system. First, we will summarize the different factors influencing its activity. Then, we will analyze the amount of data, including genome-wide, that has emerged in the recent years describing the wide variety of genes, pathways and biological functions regulated directly or indirectly by EGR1. We will thus be able to gain better insights into the mechanisms underlying EGR1's functions in physiological neuronal activity. Finally, we will discuss and illustrate the role of EGR1 in pathological states with a particular interest in cognitive functions and neuropsychiatric disorders.
Show less
Date Issued: 2017-03-06
Identifier: FSU_libsubv1_wos_000395439100001, 10.3389/fnbeh.2017.00035
Format: Citation

Title: Cd63 Regulates Epstein-barr Virus Lmp1 Exosomal Packaging, Enhancement Of Vesicle Production, And Noncanonical Nf-kappa B Signaling.
Creator: Hurwitz, Stephanie N., Nkosi, Dingani, Conlon, Meghan M., York, Sara B., Liu, Xia, Tremblay, Deanna C., Meckes, David G.
Abstract/Description: Latent membrane protein 1 (LMP1) is an Epstein-Barr virus (EBV)-encoded oncoprotein that is packaged into small extracellular vesicles (EVs) called exosomes. Trafficking of LMP1 into multivesicular bodies (MVBs) alters the content and function of exosomes. LMP1-modified exosomes enhance the growth, migration, and invasion of malignant cells, demonstrating the capacity to manipulate the tumor microenvironment and enhance the progression of EBV-associated cancers. Despite the growing evidence...
Show moreLatent membrane protein 1 (LMP1) is an Epstein-Barr virus (EBV)-encoded oncoprotein that is packaged into small extracellular vesicles (EVs) called exosomes. Trafficking of LMP1 into multivesicular bodies (MVBs) alters the content and function of exosomes. LMP1-modified exosomes enhance the growth, migration, and invasion of malignant cells, demonstrating the capacity to manipulate the tumor microenvironment and enhance the progression of EBV-associated cancers. Despite the growing evidence surrounding the significance of LMP1-modified exosomes in cancer, very little is understood about the mechanisms that orchestrate LMP1 incorporation into these vesicles. Recently, LMP1 was shown to be copurified with CD63, a conserved tetraspanin protein enriched in late endosomal and lysosomal compartments. Here, we demonstrate the importance of CD63 presence for exosomalpackaging of LMP1. Nanoparticle tracking analysis and gradient purification revealed an increase in extracellular vesicle secretion and exosomal proteins following LMP1 expression. Immunoisolation of CD63-positive exosomes exhibited accumulation of LMP1 in this vesicle population. Functionally, CRISPR/Cas9 knockout of CD63 resulted in a reduction of LMP1-induced particle secretion. Furthermore, LMP1 packaging was severely impaired in CD63 knockout cells, concomitant with a disruption in the perinuclear localization of LMP1. Importantly, LMP1 trafficking to lipid rafts and activation of NF-kappa B and PI3K/Akt pathways remained intact following CD63 knockout, while mitogen- activated protein kinase/ extracellular signal- regulated kinase (MAPK/ERK) and noncanonical NF-kappa B activation were observed to be increased. These results suggest that CD63 is a critical player in LMP1 exosomal trafficking and LMP1mediated enhancement of exosome production and may play further roles in limiting downstream LMP1 signaling. IMPORTANCE EBV is a ubiquitous gamma herpesvirus linked to malignancies such as nasopharyngeal carcinoma, Burkitt's lymphoma, and Hodgkin's lymphoma. In the context of cancer, EBV hijacks the exosomal pathway to modulate cell-to-cell signaling by secreting viral components such as an oncoprotein, LMP1, into host cell membrane-bound EVs. Trafficking of LMP1 into exosomes is associated with increased oncogenicity of these secreted vesicles. However, we have only a limited understanding of the mechanisms surrounding exosomal cargo packaging, including viral proteins. Here, we describe a role of LMP1 in EV production that requires CD63 and provide an extensive demonstration of CD63-mediated exosomal LMP1 release that is distinct from lipid raft trafficking. Finally, we present further evidence of the role of CD63 in limiting LMP1-induced noncanonical NF-kappa B and ERK activation. Our findings have implications for future investigations of physiological and pathological mechanisms of exosome biogenesis, protein trafficking, and signal transduction, especially in viral-associated tumorigenesis.
Show less
Date Issued: 2017-03
Identifier: FSU_libsubv1_wos_000394356400032, 10.1128/JVI.02251-16
Format: Citation

Title: Cellular Distribution of the Fragile X Mental Retardation Protein in the Mouse Brain.
Creator: Zorio, Diego A.R., Jackson, Christine M., Liu, Yong, Rubel, Edwin W, Wang, Yuan
Abstract/Description: The fragile X mental retardation protein (FMRP) plays an important role in normal brain development. Absence of FMRP results in abnormal neuronal morphologies in a selected manner throughout the brain, leading to intellectual deficits and sensory dysfunction in the fragile X syndrome (FXS). Despite FMRP importance for proper brain function, its overall expression pattern in the mammalian brain at the resolution of individual neuronal cell groups is not known. In this study we used FMR1...
Show moreThe fragile X mental retardation protein (FMRP) plays an important role in normal brain development. Absence of FMRP results in abnormal neuronal morphologies in a selected manner throughout the brain, leading to intellectual deficits and sensory dysfunction in the fragile X syndrome (FXS). Despite FMRP importance for proper brain function, its overall expression pattern in the mammalian brain at the resolution of individual neuronal cell groups is not known. In this study we used FMR1 knockout and isogenic wildtype mice to systematically map the distribution of FMRP expression in the entire mouse brain. Using immunocytochemistry and cellular quantification analyses, we identified a large number of prominent cell groups expressing high levels of FMRP at the subcortical levels, in particular sensory and motor neurons in the brainstem and thalamus. In contrast, many cell groups in the midbrain and hypothalamus exhibit low FMRP levels. More important, we describe differential patterns of FMRP distribution in both cortical and subcortical brain regions. Almost all major brain areas contain high and low levels of FMRP cell groups adjacent to each other or between layers of the same cortical areas. These differential patterns indicate that FMRP expression appears to be specific to individual neuronal cell groups instead of being associated with all neurons in distinct brain regions, as previously considered. Taken together, these findings support the notion of FMRP differential neuronal regulation and strongly implicate the contribution of fundamental sensory and motor processing at subcortical levels to FXS pathology.
Show less
Date Issued: 2017-03-01
Identifier: FSU_libsubv1_scholarship_submission_1511838919_1f7fa4f4, 10.1002/cne.24100
Format: Citation

Title: Proteasomes, caught in the act.
Creator: Tomko, Robert J
Abstract/Description: Although energy-dependent protein destruction by the proteasome has been known for over 30 years, how this intricate molecular machine uses ATP to power protein degradation has remained very poorly understood. In a recently published paper, Ding et al. present a snapshot of the proteasome mid-catalysis, yielding new and unexpected insights into the catalytic mechanism of this ATP-powered multisubunit machine.
Date Issued: 2017-03-01
Identifier: FSU_pmch_28220774, 10.1038/cr.2017.22, PMC5339839, 28220774, 28220774, cr201722
Format: Citation

Title: Premature Silencing of the Spindle Assembly Checkpoint Is Prevented by the Bub1-H2A-Sgo1-PP2A Axis in .
Creator: Jin, Fengzhi, Bokros, Michael, Wang, Yanchang
Abstract/Description: The spindle assembly checkpoint (SAC) monitors mistakes in kinetochore-microtubule interaction and its activation prevents anaphase entry. The SAC remains active until all chromosomes have achieved bipolar attachment which applies tension on kinetochores. Our previous data in budding yeast show that Ipl1/Aurora B kinase and a centromere-associated protein, Sgo1, are required to prevent SAC silencing prior to tension generation, but we believe that this regulatory network is incomplete. Bub1...
Show moreThe spindle assembly checkpoint (SAC) monitors mistakes in kinetochore-microtubule interaction and its activation prevents anaphase entry. The SAC remains active until all chromosomes have achieved bipolar attachment which applies tension on kinetochores. Our previous data in budding yeast show that Ipl1/Aurora B kinase and a centromere-associated protein, Sgo1, are required to prevent SAC silencing prior to tension generation, but we believe that this regulatory network is incomplete. Bub1 kinase is one of the SAC components, and Bub1-dependent H2A phosphorylation triggers centromere recruitment of Sgo1 by H2A in yeast and human cells. Although yeast cells lacking the kinase domain of Bub1 show competent SAC activation, we found that the mutant cells fail to maintain a prolonged checkpoint arrest in the presence of tensionless attachment. Mutation of the Bub1 phosphorylation site in H2A also results in premature SAC silencing in yeast cells. Previous data indicate that Sgo1 protein binds to PP2A, and we found that Δ mutants exhibited premature SAC silencing as well. We further revealed that mutants with abolished binding to H2A or PP2A displayed premature SAC silencing. Together, our results suggest that, in budding yeast , the Bub1-H2A-Sgo1-PP2A axis prevents SAC silencing and helps prolonged checkpoint arrest prior to tension establishment at kinetochores.
Show less
Date Issued: 2017-03-01
Identifier: FSU_pmch_28040741, 10.1534/genetics.116.195727, PMC5340331, 28040741, 28040741, genetics.116.195727
Format: Citation

Title: Cellular distribution of the fragile X mental retardation protein in the mouse brain.
Creator: Zorio, Diego A R, Jackson, Christine M, Liu, Yong, Rubel, Edwin W, Wang, Yuan
Abstract/Description: The fragile X mental retardation protein (FMRP) plays an important role in normal brain development. Absence of FMRP results in abnormal neuronal morphologies in a selected manner throughout the brain, leading to intellectual deficits and sensory dysfunction in the fragile X syndrome (FXS). Despite FMRP importance for proper brain function, its overall expression pattern in the mammalian brain at the resolution of individual neuronal cell groups is not known. In this study we used FMR1...
Show moreThe fragile X mental retardation protein (FMRP) plays an important role in normal brain development. Absence of FMRP results in abnormal neuronal morphologies in a selected manner throughout the brain, leading to intellectual deficits and sensory dysfunction in the fragile X syndrome (FXS). Despite FMRP importance for proper brain function, its overall expression pattern in the mammalian brain at the resolution of individual neuronal cell groups is not known. In this study we used FMR1 knockout and isogenic wildtype mice to systematically map the distribution of FMRP expression in the entire mouse brain. Using immunocytochemistry and cellular quantification analyses, we identified a large number of prominent cell groups expressing high levels of FMRP at the subcortical levels, in particular sensory and motor neurons in the brainstem and thalamus. In contrast, many cell groups in the midbrain and hypothalamus exhibit low FMRP levels. More important, we describe differential patterns of FMRP distribution in both cortical and subcortical brain regions. Almost all major brain areas contain high and low levels of FMRP cell groups adjacent to each other or between layers of the same cortical areas. These differential patterns indicate that FMRP expression appears to be specific to individual neuronal cell groups instead of being associated with all neurons in distinct brain regions, as previously considered. Taken together, these findings support the notion of FMRP differential neuronal regulation and strongly implicate the contribution of fundamental sensory and motor processing at subcortical levels to FXS pathology. J. Comp. Neurol. 525:818-849, 2017. © 2016 Wiley Periodicals, Inc.
Show less
Date Issued: 2017-03-01
Identifier: FSU_pmch_27539535, 10.1002/cne.24100, PMC5558202, 27539535, 27539535
Format: Citation

Search In

Pages

Pages

Sort Results By:

Narrow results by:

Collection

Topical Subject

Genre

Type of Resource

Language

Creator

Found In

Owner

Animals (120)	+ -
Humans (68)	+ -
Male (60)	+ -
Mice (46)	+ -
Female (36)	+ -

text (312)	+ -
journal article (263)	+ -
working paper (2)	+ -