Article

Dnmt3a is essential for hematopoietic stem cell differentiation.

Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, Texas, USA.
Nature Genetics (Impact Factor: 29.65). 12/2011; 44(1):23-31. DOI: 10.1038/ng.1009
Source: PubMed

ABSTRACT Loss of the de novo DNA methyltransferases Dnmt3a and Dnmt3b in embryonic stem cells obstructs differentiation; however, the role of these enzymes in somatic stem cells is largely unknown. Using conditional ablation, we show that Dnmt3a loss progressively impairs hematopoietic stem cell (HSC) differentiation over serial transplantation, while simultaneously expanding HSC numbers in the bone marrow. Dnmt3a-null HSCs show both increased and decreased methylation at distinct loci, including substantial CpG island hypermethylation. Dnmt3a-null HSCs upregulate HSC multipotency genes and downregulate differentiation factors, and their progeny exhibit global hypomethylation and incomplete repression of HSC-specific genes. These data establish Dnmt3a as a critical participant in the epigenetic silencing of HSC regulatory genes, thereby enabling efficient differentiation.

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