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Updated: Jul 5, 2026
10:36
Chromatin Immunoprecipitation from Human Embryonic Stem Cells
Published on: July 22, 2008
Chromatin remodeling during mouse and human embryonic stem cell differentiation
Jonathan L Golob1, Sharon L Paige, Veronica Muskheli
1Department of Pathology, Center for Cardiovascular Biology, Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington 98109, USA.
Summary
Embryonic stem cell (ESC) differentiation involves dynamic chromatin changes. Key developmental genes like Brachyury T switch between active euchromatin and inactive heterochromatin states during differentiation.
Area of Science:
- Developmental Biology
- Epigenetics
- Stem Cell Biology
Background:
- Embryonic stem cell (ESC) differentiation offers insights into chromatin modifications at developmentally regulated genes.
- During differentiation, ESCs exhibit genome-wide increases in euchromatin (acetylation) and heterochromatin (histone H3 lysine 9 trimethylation).
Purpose of the Study:
- To investigate chromatin dynamics at the Brachyury T locus during human ESC differentiation.
- To understand the role of specific histone modifications in regulating mesendoderm development.
Main Methods:
- Analysis of histone modifications (trimethylation and acetylation) at the Oct4 and Brachyury T loci in undifferentiated and differentiating human ESCs.
- Directed differentiation protocols to induce mesoderm and endoderm lineages.
Main Results:
- The Oct4 locus is euchromatic in undifferentiated ESCs and heterochromatic upon differentiation.
- The Brachyury T locus displays bivalent histone modifications in undifferentiated ESCs.
- During differentiation, the Brachyury T locus transitions from euchromatin to heterochromatin following activation and subsequent silencing.
Conclusions:
- ESC differentiation is characterized by a genome-wide commitment to euchromatin or heterochromatin.
- The study provides the first analysis of chromatin dynamics at the Brachyury T locus during mesendoderm differentiation.
- Dynamic chromatin remodeling at key developmental loci is crucial for lineage specification.
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