Smc3 acetylation, Pds5 and Scc2 control the translocase activity that establishes cohesin-dependent chromatin loops

Cohesin is a DNA translocase that is instrumental in the folding of the genome into chromatin loops, with functional consequences on DNA-related processes. Chromatin loop length and organization likely depend on cohesin processivity, translocation rate and stability on DNA. Here, we investigate and provide a comprehensive overview of the roles of various cohesin regulators in tuning chromatin loop expansion in budding yeast Saccharomyces cerevisiae. We demonstrate that Scc2, which stimulates cohesin ATPase activity, is also essential for cohesin translocation, driving loop expansion in vivo. Smc3 acetylation during the S phase counteracts this activity through the stabilization of Pds5, which finely tunes the size and stability of loops in G2.

Automated summary

This study investigates the roles of various cohesin regulators in tuning chromatin loop expansion in budding yeast, revealing that Scc2 plays a key role in both stimulating cohesin ATPase activity and driving cohesin translocation on DNA, while Smc3 acetylation during S phase counteracts this activity by stabilizing Pds5 to finely tune loop size and stability in G2.