Smchd1 Targeting to the Inactive X Is Dependent on the Xist-HnrnpK-PRC1 Pathway

Natasha Jansz, Tatyana Nesterova, Andrew Keniry, Megan Iminitoff, Peter F. Hickey, Greta Pintacuda, Osamu Masui, Simon Kobelke, Niall Geoghegan, Kelsey A. Breslin, Tracy A. Willson, Kelly Rogers, Graham F. Kay, Archa H. Fox, Haruhiko Koseki, Neil Brockdorff, James M. Murphy, Marnie E. Blewitt

Research output: Contribution to journalArticlepeer-review

46 Citations (Scopus)


We and others have recently reported that the SMC protein Smchd1 is a regulator of chromosome conformation. Smchd1 is critical for the structure of the inactive X chromosome and at autosomal targets such as the Hox genes. However, it is unknown how Smchd1 is recruited to these sites. Here, we report that Smchd1 localizes to the inactive X via the Xist-HnrnpK-PRC1 (polycomb repressive complex 1) pathway. Contrary to previous reports, Smchd1 does not bind Xist or other RNA molecules with any specificity. Rather, the localization of Smchd1 to the inactive X is H2AK119ub dependent. Following perturbation of this interaction, Smchd1 is destabilized, which has consequences for gene silencing genome-wide. Our work adds Smchd1 to the PRC1 silencing pathway for X chromosome inactivation. Jansz et al. report that the chromatin protein Smchd1 depends on polycomb repressive complex 1-mediated ubiquitylation of histone H2A for its recruitment to the inactive X chromosome and for its protein stability. These data have implications for Smchd1 targeting genome-wide.

Original languageEnglish
Pages (from-to)1912-1923.e9
JournalCell Reports
Issue number7
Publication statusPublished - 13 Nov 2018


Dive into the research topics of 'Smchd1 Targeting to the Inactive X Is Dependent on the Xist-HnrnpK-PRC1 Pathway'. Together they form a unique fingerprint.

Cite this