Getting off the ground state: X chromosome inactivation knocks down barriers to differentiation
Robert Morey1, Louise C Laurent1
1Department of Reproductive Medicine, University of California, San Diego, Sanford Consortium for Regenerative Medicine, 2880 Torrey Pines Scenic Drive, La Jolla, CA 92037, USA.
Cell Stem Cell
|February 11, 2014
Summary
Female mouse stem cells with two active X chromosomes stay pluripotent by blocking MAPK signaling. This ensures X chromosome dosage compensation aligns with developmental timing.
Area of Science:
- Developmental Biology
- Epigenetics
- Stem Cell Biology
Background:
- Female mouse embryonic stem cells (mESCs) possess two active X chromosomes.
- X chromosome inactivation is a key process during differentiation.
- The link between X chromosome status and pluripotency exit is not fully understood.
Purpose of the Study:
- To investigate how two active X chromosomes influence mESC pluripotency.
- To determine the role of MAPK signaling in this process.
- To understand the synchronization of X chromosome dosage compensation and development.
Main Methods:
- Utilized mESCs with two active X chromosomes.
- Investigated the impact of active X chromosomes on MAPK signaling pathways.
- Assessed the effects on pluripotency exit and differentiation.
Main Results:
- The presence of two active X chromosomes in mESCs actively prevents exit from pluripotency.
- This block is mediated by the inhibition of MAPK signaling.
- Active X chromosomes ensure that X chromosome dosage compensation is synchronized with developmental progression.
Conclusions:
- Two active X chromosomes maintain mESC pluripotency by suppressing MAPK signaling.
- This mechanism ensures proper coordination between epigenetic regulation (X inactivation) and developmental timing.
- Findings provide critical insights into the regulation of pluripotency and early development.
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