Schizosaccharomyces pombe Cds1Chk2 regulates homologous recombination at stalled replication forks through the phosphorylation of recombination protein Rad60.
The Schizosaccharomyces pombe rad60 gene is essential for cell growth and is involved in repairing DNA double-strand breaks. Rad60 physically interacts with, and is functionally related to, the structural maintenance of chromosomes 5 and 6 protein complex (Smc5/6). Rad60 is phosphorylated in response to hydroxyurea (HU)-induced DNA replication arrest in a Cds1(Chk2)-dependent manner. Rad60 localizes in nucleus in unchallenged cells, but becomes diffused throughout the cell in response to HU. To understand the role of Rad60 phosphorylation, we mutated the putative phosphorylation target motifs of Cds1(Chk2) and have identified two Cds1(Chk2) target residues responsible for Rad60 dispersal in response to HU. We show that the phosphorylation-defective rad60 mutation partially suppresses HU sensitivity and the elevated recombination frequency of smc6-X. Our data suggest that Rad60 phosphorylation is required to regulate homologous recombination at stalled replication forks, probably by regulating Smc5/6.
Miyabe
Izumi
I
Genome Damage and Stability Centre, University of Sussex, Brighton BN1 9RQ, UK.
Morishita
Takashi
T
Shinagawa
Hideo
H
Carr
Antony M
AM
D018797:Cell Cycle Proteins / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D064447:Checkpoint Kinase 2; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004249:DNA Damage; D004261:DNA Replication / Q000187:drug effects; D004275:DNA, Ribosomal / Q000378:metabolism; D006918:Hydroxyurea / Q000494:pharmacology; D050296:Microbial Viability / Q000187:drug effects; D009153:Mutagens / Q000633:toxicity; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D011995:Recombination, Genetic / Q000187:drug effects; D012568:Schizosaccharomyces / Q000166:cytology / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*; D012694:Serine / Q000378:metabolism; D013912:Threonine / Q000378:metabolism
D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004275:DNA, Ribosomal; D009153:Mutagens; C455501:Rad60 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; C486630:smc6 protein, S pombe; D013912:Threonine; D012694:Serine; D064447:Checkpoint Kinase 2; C578636:Cds1 protein, S pombe; D017346:Protein Serine-Threonine Kinases; D006918:Hydroxyurea