Proteasome nuclear activity affects chromosome stability by controlling the turnover of Mms22, a protein important for DNA repair.

ABSTRACT: To expand the known spectrum of genes that maintain genome stability, we screened a recently released collection of temperature sensitive (Ts) yeast mutants for a chromosome instability (CIN) phenotype. Proteasome subunit genes represented a major functional group, and subsequent analysis demonstrated an evolutionarily conserved role in CIN. Analysis of individual proteasome core and lid subunit mutations showed that the CIN phenotype at semi-permissive temperature is associated with failure of subunit localization to the nucleus. The resultant proteasome dysfunction affects chromosome stability by impairing the kinetics of double strand break (DSB) repair. We show that the DNA repair protein Mms22 is required for DSB repair, and recruited to chromatin in a ubiquitin-dependent manner as a

SUBMITTER: Ben-Aroya S 

PROVIDER: S-EPMC2824753 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature