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Cohesin causes replicative DNA damage by trapping DNA topological stress

ABSTRACT: DNA topological stress inhibits DNA replication fork (RF) progression and contributes to DNA replication stress. In Saccharomyces cerevisiae we demonstrate that centromeric DNA and the rDNA array are especially vulnerable to DNA topological stress during replication. The activity of the SMC complexes cohesin and condensin are linked to both the generation and repair of DNA topological stress linked damage in these regions. At cohesin enriched centromeres cohesin activity causes the accumulation of DNA damage, RF rotation and precatenation, confirming that cohesin dependent DNA topological stress impacts on normal replication progression. In contrast, at the rDNA cohesin and condensin activity inhibit the repair of damage caused by DNA topological stress. We propose that as well as generally acting to ensure faithful genetic inheritance, SMCs can disrupt genome stability by trapping DNA topological stress.

ORGANISM(S): Saccharomyces cerevisiae Schizosaccharomyces pombe

PROVIDER: GSE131558 | GEO | 2020/03/03

REPOSITORIES: GEO

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