Break-induced replication requires all essential DNA replication factors except those specific for pre-RC assembly.
Break-induced replication (BIR) is an efficient homologous recombination (HR) pathway employed to repair a DNA double-strand break (DSB) when homology is restricted to one end. All three major replicative DNA polymerases are required for BIR, including the otherwise nonessential Pol32 subunit. Here we show that BIR requires the replicative DNA helicase (Cdc45, the GINS, and Mcm2-7 proteins) as well as Cdt1. In contrast, both subunits of origin recognition complex (ORC) and Cdc6, which are required to create a prereplication complex (pre-RC), are dispensable. The Cdc7 kinase, required for both initiation of DNA replication and post-replication repair (PRR), is also required for BIR. Ubiquitination and sumoylation of the DNA processivity clamp PCNA play modest roles; in contrast, PCNA alleles that suppress pol32Delta's cold sensitivity fail to suppress its role in BIR, and are by themselves dominant inhibitors of BIR. These results suggest that origin-independent BIR involves cross-talk between normal DNA replication factors and PRR.
Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02454, USA.
John R
JR
Lydeard
Zachary
Z
Lipkin-Moore
Yi-Jun
YJ
Sheu
Bruce
B
Stillman
Peter M
PM
Burgers
James E
JE
Haber
D000483:Alleles; D018797:Cell Cycle Proteins / Q000378:metabolism; D003080:Cold Temperature; D053903:DNA Breaks, Double-Stranded; D004265:DNA Helicases / Q000378:metabolism; D004260:DNA Repair / Q000235:genetics / Q000502:physiology; D004261:DNA Replication / Q000235:genetics / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D009154:Mutation; D051738:Origin Recognition Complex / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D025842:SUMO-1 Protein / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D054875:Ubiquitination
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D051738:Origin Recognition Complex; D025842:SUMO-1 Protein; D029701:Saccharomyces cerevisiae Proteins; C499592:TAH11 protein, S cerevisiae; C068619:CDC7 protein, human; D017346:Protein Serine-Threonine Kinases; D004265:DNA Helicases