The DNA damage and the DNA synthesis checkpoints converge at the MBF transcription factor

DNA damage is an ongoing threat to both the ability of the cell to faithfully transmit genetic information to its offspring as well as to its own survival. In order to maintain genomic integrity, eukaryotes have developed a highly conserved mechanism to detect, signal and repair damage in DNA, known...

Full description

Bibliographic Details
Author: Ivanova, Tsvetomira Georgieva
Format: doctoral thesis
Status:Published version
Publication Date:2012
Country:España
Institution:CBUC, CESCA
Repository:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/116932
Online Access:http://hdl.handle.net/10803/116932
Access Level:Open access
Keyword:Levadura
Schizosaccharomyces pombe
Replicación
Transcripción
Factor de transcripción
Ciclo celular
Checkpoint
Daño en DNA
Fosforilación
Kinasa
Yeast
Replication
Transcription
Transcription factor
Cell Cycle
DNA damage
Phosphorylation
Kinase
575
Description
Summary:DNA damage is an ongoing threat to both the ability of the cell to faithfully transmit genetic information to its offspring as well as to its own survival. In order to maintain genomic integrity, eukaryotes have developed a highly conserved mechanism to detect, signal and repair damage in DNA, known as the DNA damage response (DDR). In fission yeast the two DDR pathways converge at the regulation of single transcriptional factor complex (MBF) resulting in opposite directions. We have shown that when the DNA-synthesis checkpoint is activated, Max1 is phosphorylated by Cds1 resulting in the abrogation of its binding to MBF. As a consequence, MBF-dependent transcription is maintained active until cells are able to overcome the replication challenge. In contrast, upon DNA damage, Chk1 the effector kinase of DNA damage checkpoint is activated and blocks the cell cycle progression, inducing DNA repair and repressing the MBF dependent transcription. We have revealed that Cdc10 is the target of the DNA-damage checkpoint and when cells are treated with MMS or are exposed to IR, Chk1 phosphorylates Cdc10 inducing the exit of MBF from chromatin. The consequence is that under these conditions, MBF-dependent transcription is repressed. Thus, Max1 and Cdc10 couple normal cell cycle regulation and the DNA-synthesis and DNA-damage checkpoints into MBF.