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Title: The yeast Dbf4 Zn2+ finger domain suppresses single-stranded DNA at replication forks initiated from a subset of origins
Abstract

Dbf4 is the cyclin-like subunit for the Dbf4-dependent protein kinase (DDK), required for activating the replicative helicase at DNA replication origin that fire during S phase. Dbf4 also functions as an adaptor, targeting the DDK to different groups of origins and substrates. Here we report a genome-wide analysis of origin firing in a budding yeast mutant,dbf4-zn, lacking the Zn2+finger domain within the C-terminus of Dbf4. At one group of origins, which we call dromedaries, we observe an unanticipated DNA replication phenotype: accumulation of single-stranded DNA spanning ± 5kbp from the center of the origins. A similar accumulation of single-stranded DNA at origins occurs more globally inpri1-m4mutants defective for the catalytic subunit of DNA primase andrad53mutants defective for the S phase checkpoint following DNA replication stress. We propose the Dbf4 Zn2+finger suppresses single-stranded gaps at replication forks emanating from dromedary origins. Certain origins may impose an elevated requirement for the DDK to fully initiate DNA synthesis following origin activation. Alternatively,dbf4-znmay be defective for stabilizing/restarting replication forks emanating from dromedary origins during replication stress.

 
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PAR ID:
10364569
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Springer Science + Business Media
Date Published:
Journal Name:
Current Genetics
Volume:
68
Issue:
2
ISSN:
0172-8083
Page Range / eLocation ID:
p. 253-265
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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