MOF-associated complexes ensure stem cell identity and Xist repression
- Max Planck Institute for Immunobiology and Epigenetics, Germany
- Institute Curie, France
- University of Freiburg, Germany
- Institut Curie, France
Abstract
Histone acetyl transferases (HATs) play distinct roles in many cellular processes and are frequently misregulated in cancers. Here, we study the regulatory potential of MYST1-(MOF)-containing MSL and NSL complexes in mouse embryonic stem cells (ESCs) and neuronal progenitors. We find that both complexes influence transcription by targeting promoters as well as TSS-distal enhancers. In contrast to flies, the MSL complex is not exclusively enriched on the X chromosome yet it is crucial for mammalian X chromosome regulation as it specifically regulates Tsix, the major repressor of Xist lncRNA. MSL depletion leads to decreased Tsix expression, reduced REX1 recruitment, and consequently, enhanced accumulation of Xist and variable numbers of inactivated X chromosomes during early differentiation. The NSL complex provides additional, Tsix-independent repression of Xist by maintaining pluripotency. MSL and NSL complexes therefore act synergistically by using distinct pathways to ensure a fail-safe mechanism for the repression of X inactivation in ESCs.
Article and author information
Author details
Reviewing Editor
- Danny Reinberg, Howard Hughes Medical Institute, New York University School of Medicine, United States
Version history
- Received: December 6, 2013
- Accepted: May 11, 2014
- Accepted Manuscript published: May 19, 2014 (version 1)
- Version of Record published: June 17, 2014 (version 2)
Copyright
© 2014, Chelmicki et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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MOF-associated complexes ensure stem cell identity and Xist repression
eLife 3:e02024.
https://doi.org/10.7554/eLife.02024
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