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Isolation and Cultivation of Neural Progenitors Followed by Chromatin-Immunoprecipitation of Histone 3 Lysine 79 Dimethylation Mark
Published on: January 26, 2018
Differential H3K4 methylation identifies developmentally poised hematopoietic genes
Keith Orford1, Peter Kharchenko, Weil Lai
1Center for Regenerative Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
Developmental Cell
|May 15, 2008
Summary
Histone modifications like H3K4me2 and H3K4me3 are crucial for cell identity. Differential methylation marks silent hematopoietic genes, revealing distinct epigenetic regulation during development.
Area of Science:
- Epigenetics
- Developmental Biology
- Genomics
Background:
- Cell fate decisions during development are encoded by epigenetic information.
- Heritable epigenetic marks, such as covalent histone modifications, are critical for establishing cellular identity.
- Histone H3 lysine 4 dimethylation (H3K4me2) and trimethylation (H3K4me3) are key epigenetic marks.
Purpose of the Study:
- To assess the genome-wide concordance of H3K4me2 and H3K4me3 during erythroid development.
- To investigate the role of differential H3K4 methylation in lineage-specific gene regulation.
- To explore the relationship between DNA sequence and epigenetic marks in cell differentiation.
Main Methods:
- Genome-wide analysis of H3K4me2 and H3K4me3.
- Comparative analysis across pluripotent, multipotent, and unipotent cell types during erythroid development.
- Identification and characterization of differentially methylated genes.
Main Results:
- H3K4me2 and H3K4me3 are largely concordant across genes.
- A subset of genes in multipotential hematopoietic cells exhibits differential methylation (H3K4me2+/me3-).
- These differentially methylated genes are transcriptionally silent, enriched in hematopoietic lineages, and susceptible to demethylation during differentiation.
- Embryonic stem cells lack these differentially methylated genes and restrict H3K4 methylation to CpG islands (CGIs).
Conclusions:
- Distinct epigenetic regulation exists for CGI and non-CGI genes during development.
- Differential H3K4 methylation plays a role in lineage-specific hematopoietic gene silencing.
- An interaction between DNA sequence and H3K4 methylation patterns influences lineage commitment.
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