SWI/SNF-Brg1 regulates self-renewal and occupies core pluripotency-related genes in embryonic stem cells.
The SWI/SNF-Brg1 chromatin remodeling protein plays critical roles in cell-cycle control and differentiation through regulation of gene expression. Loss of Brg1 in mice results in early embryonic lethality, and recent studies have implicated a role for Brg1 in somatic stem cell self-renewal and differentiation. However, little is known about Brg1 function in preimplantation embryos and embryonic stem (ES) cells. Here we report that Brg1 is required for ES cell self-renewal and pluripotency. RNA interference-mediated knockdown of Brg1 in blastocysts caused aberrant expression of Oct4 and Nanog. In ES cells, knockdown of Brg1 resulted in phenotypic changes indicative of differentiation, downregulation of self-renewal and pluripotency genes (e.g., Oct4, Sox2, Sall4, Rest), and upregulation of differentiation genes. Using genome-wide promoter analysis (chromatin immunoprecipitation) we found that Brg1 occupied the promoters of key pluripotency-related genes, including Oct4, Sox2, Nanog, Sall4, Rest, and Polycomb group (PcG) proteins. Moreover, Brg1 co-occupied a subset of Oct4, Sox2, Nanog, and PcG protein target genes. These results demonstrate an important role for Brg1 in regulating self-renewal and pluripotency in ES cells.
Kidder
Benjamin L
BL
EMD Serono Research Institute, Inc., Rockland, Massachusetts, USA.
Palmer
Stephen
S
Knott
Jason G
JG
D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism*; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000235:genetics / Q000502:physiology*; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D002868:Chromosomal Proteins, Non-Histone; D009687:Nuclear Proteins; C445179:SWI-SNF-B chromatin-remodeling complex; D014157:Transcription Factors; C513194:Smarca4 protein, mouse; D004265:DNA Helicases