PRC1 collaborates with SMCHD1 to fold the X-chromosome and spread Xist RNA between chromosome compartments

Abstract

The inactive X (Xi)-specific S1/S2 chromosome compartments are merged by SMCHD1, but how the S1/S2 structure is constructed is unclear. The authors find that PRC1 drives the formation of S1/S2s and that the stepwise folding process of the Xi facilitates Xist RNA spreading between Xi compartments.