Abstract
The Saccharomyces cerevisiae Rad53 protein kinase is required for the execution of checkpoint arrest at multiple stages of the cell cycle. We found that Rad53 autophosphorylation activity depends on in trans phosphorylation mediated by Mec1 and does not require physical association with other proteins. Uncoupling in trans phosphorylation from autophosphorylation using a rad53 kinase-defective mutant results in a dominant-negative checkpoint defect. Activation of Rad53 in response to DNA damage in G1 requires the Rad9, Mec3, Ddc1, Rad17 and Rad24 checkpoint factors, while this dependence is greatly reduced in S phase cells. Furthermore, during recovery from checkpoint activation, Rad53 activity decreases through a process that does not require protein synthesis. We also found that Rad53 modulates the lagging strand replication apparatus by controlling phosphorylation of the DNA polymerase α-primase complex in response to intra-S DNA damage.
Original language | English |
---|---|
Pages (from-to) | 6561-6572 |
Number of pages | 12 |
Journal | EMBO Journal |
Volume | 18 |
Issue number | 22 |
DOIs | |
Publication status | Published - Nov 15 1999 |
Keywords
- Checkpoints
- DNA damage
- DNA polymerase α-primase
- DNA replication
- Rad53
ASJC Scopus subject areas
- Genetics
- Cell Biology