You are here

Dpb11 may function with RPA and DNA to initiate DNA replication.

Title: Dpb11 may function with RPA and DNA to initiate DNA replication.
Name(s): Bruck, Irina, author
Dhingra, Nalini, author
Martinez, Matthew P, author
Kaplan, Daniel L, author
Type of Resource: text
Genre: Journal Article
Date Issued: 2017-05-03
Physical Form: computer
online resource
Extent: 1 online resource
Language(s): English
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, 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.
Identifier: FSU_pmch_28467467 (IID), 10.1371/journal.pone.0177147 (DOI), PMC5415106 (PMCID), 28467467 (RID), 28467467 (EID), PONE-D-17-03239 (PII)
Grant Number: R15 GM113167
Publication Note: This NIH-funded author manuscript originally appeared in PubMed Central at
Persistent Link to This Record:
Host Institution: FSU
Is Part Of: PloS one.
Issue: iss. 5, vol. 12

Choose the citation style.
Bruck, I., Dhingra, N., Martinez, M. P., & Kaplan, D. L. (2017). Dpb11 may function with RPA and DNA to initiate DNA replication. Plos One. Retrieved from