Cohesin residence time gates 3D genome response to histone hyperacetylation

Cohesin-mediated loop extrusion and chromatin state-dependent compartmentalization are major drivers of three-dimensional (3D) genome organization. Although epigenomic perturbations are widely assumed to reshape chromatin architecture, the mechanisms that determine how changes in chromatin state are translated into structural reorganization remain poorly understood. Here, we identify cohesin residence time as a key regulator of the genome's architectural response to histone hyperacetylation induced by histone deacetylase inhibition (HDACi). Acute depletion of RAD21 or CTCF weakens chromatin loops but preserves HDACi-induced changes in compartmentalization, contact-scaling behavior, and loop