The pluripotent genome is characterized by unique epigenetic features and a decondensed chromatin conformation. However, the relationship between epigenetic regulation and pluripotency is not altogether clear. Here, using an enhanced MEF/ESC fusion protocol, we compared the reprogramming potency and histone modifications of different embryonic stem cell (ESC) lines (R1, J1, E14, C57BL/6) and found that E14 ESCs are significantly less potent, with significantly reduced H3K9ac levels. Treatment of E14 ESCs with histone deacetylase (HDAC) inhibitors (HDACi) increased H3K9ac levels and restored their reprogramming capacity. Microarray and H3K9ac ChIP-seq analyses, suggested increased extracellular matrix (ECM) activity following HDACi treatment in E14 ESCs. These data suggest that H3K9ac may predict pluripotency and that increasing pluripotency by HDAC inhibition acts through H3K9ac to enhance the activity of target genes involved in ECM production to support pluripotency.
Bibliographical noteFunding Information:
The authors would like to thank Asher Meshorer for histopathological analyses and Evgenia Leikina for technical assistant with the fusion protocols and for helpful comments. This work was supported by funds from the intramural research program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development/NIH/HHS, the Israel Science Foundation (215/07 and 943/09) (to E.M.); the Israel Ministry of Health (6007) (to E.M.), the EU (IRG-206872 and 238176) (to E.M.), the ICRF (to A.M. and E.M.), The HUJI Internal Applicative Medical Grants (to E.M.), the Israeli Psychobiology Institute (to E.M.) and an Alon Fellowship (to E.M.). E.M. is a Joseph H. and Belle R. Braun Senior Lecturer in Life Sciences. H.H. is an Edmond J. Safra Fellow.
- Chromatin plasticity
- Embryonic stem cells
- Histone acetylation
- Histone modifications