Tight protein–DNA interactions favor gene silencing

1 juil. 2011Genes & Development

DOI : 10.1101/gad.611011

Auteurs

Marion Dubarry, Isabelle LoĂŻodice, Chunlong L. Chen, Claude Thermes, Angela Taddei

Résumé

The heterochromatin-like structure formed by the yeast silent information regulator complex (SIR) represses transcription at the silent mating type loci and telomeres. Here, we report that tight protein–DNA complexes induce ectopic recruitment of the SIR complex, promoting gene silencing and changes in subnuclear localization when cis-acting elements are nearby. Importantly, lack of the replication fork-associated helicase Rrm3 enhances this induced gene repression. Additionally, Sir3 and Sir4 are enriched genome-wide at natural replication pause sites, including tRNA genes. Consistently, inserting a tRNA gene promotes SIR-mediated silencing of a nearby gene. These results reveal that replication stress arising from tight DNA–protein interactions favors heterochromatin formation.

Membres

ANGELA TADDEI

Directeur de recherche CNRS

CHUNLONG CHEN

Directeur de recherche CNRS