Premium
Srs2 DNA helicase is involved in checkpoint response and its regulation requires a functional Mec1‐dependent pathway and Cdk1 activity
Author(s) -
Liberi Giordano,
Chiolo Irene,
Pellicioli Achille,
Lopes Massimo,
Plevani Paolo,
MuziFalconi Marco,
Foiani Marco
Publication year - 2000
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1093/emboj/19.18.5027
Subject(s) - biology , helicase , g2 m dna damage checkpoint , checkpoint kinase 2 , microbiology and biotechnology , genetics , dna , cell cycle checkpoint , cell cycle , gene , rna
In Saccharomyces cerevisiae the rate of DNA replication is slowed down in response to DNA damage as a result of checkpoint activation, which is mediated by the Mec1 and Rad53 protein kinases. We found that the Srs2 DNA helicase, which is involved in DNA repair and recombination, is phosphorylated in response to intra‐S DNA damage in a checkpoint‐dependent manner. DNA damage‐induced Srs2 phosphorylation also requires the activity of the cyclin‐dependent kinase Cdk1, suggesting that the checkpoint pathway might modulate Cdk1 activity in response to DNA damage. Moreover, srs2 mutants fail to activate Rad53 properly and to slow down DNA replication in response to intra‐S DNA damage. The residual Rad53 activity observed in srs2 cells depends upon the checkpoint proteins Rad17 and Rad24. Moreover, DNA damage‐induced lethality in rad17 mutants depends partially upon Srs2, suggesting that a functional Srs2 helicase causes accumulation of lethal events in a checkpoint‐defective context. Altogether, our data implicate Srs2 in the Mec1 and Rad53 pathway and connect the checkpoint response to DNA repair and recombination.