Saccharomyces cells with one unrepaired double-strand break (DSB) adapt after checkpoint-mediated G2/M arrest. Adaptation is accompanied by loss of Rad53p checkpoint kinase activity and Chk1p phosphorylation. Rad53p kinase remains elevated in yku70Δ and cdc5-ad cells that fail to adapt. Permanent G2/M arrest in cells with increased single-stranded DNA is suppressed by the rfa1-t11 mutation, but this RPA mutation does not suppress permanent arrest in cdc5-ad cells. Checkpoint kinase activation and inactivation can be followed in G2-arrested cells, but there is no kinase activation in G1-arrested cells. We conclude that activation of the checkpoint kinases in response to a single DNA break is cell cycle regulated and that adaptation is an active process by which these kinases are inactivated.
|Titolo:||Regulation of Saccharomyces Rad53 checkpoint kinase during adaptation from DNA damage-induced G2/M arrest|
PELLICIOLI, ACHILLE (Primo)
FOIANI, MARCO (Penultimo)
|Data di pubblicazione:||2001|
|Digital Object Identifier (DOI):||10.1016/S1097-2765(01)00177-0|
|Appare nelle tipologie:||01 - Articolo su periodico|