Project description:We performed ChIP-seq to chart genome-wide maps of H3K27me3 in brown preadipocytes and mature brown adipocytes. We observed a subset of brown fat-specific genes, but not common fat genes or white fat-specific genes, possess the H3K27me3 mark in preadipocytes, and this mark is erased in mature adipocytes. H3K27me3 ChIP-seq in brown preadipocytes and mature adipocytes.
Project description:Brown adipocytes, muscle and dorsal dermis descend from precursor cells in the dermomyotome, but the factors that regulate commitment to the brown adipose lineage are unknown. Here, we prospectively isolated and determined the molecular profile of embryonic brown preadipose cells. Brown adipogenic precursor activity in embryos was confined to Pdgfrα+, Myf5Cre-lineage-marked cells. RNAseq analysis identified Early B Cell Factor-2 (Ebf2) as one of the most selectively expressed genes in this cell fraction. Importantly, Ebf2-expressing cells purified from Ebf2-GFP embryos or brown fat tissue did not express myoblast or dermal cell markers and uniformly differentiated into brown adipocytes. Interestingly, Ebf2-expressing cells from white fat tissue in adult animals differentiated into brown-like (or beige) adipocytes. Loss of Ebf2 in brown preadipose cells reduced the expression levels of brown preadipose-signature genes, whereas ectopic Ebf2-expression in myoblasts activated brown preadipose-specific genes. Altogether, these results indicate that Ebf2 specifically marks and regulates the molecular profile of brown preadipose cells. Embryonic fibroblasts, isolated from dorsal body wall of E14.5 Myf5-CrE;mTmG embryos, were further fractionated based on the expression of PDGFRα, Itga7 and Myf5-cre (GFP). Total mRNA profiles from Myf5-cre(GFP)+PDGFRα+ and Myf5-cre(GFP)+PDGFRα-Itga7+ cells were generated by deep sequenceing
Project description:Brown adipocytes, muscle and dorsal dermis descend from precursor cells in the dermomyotome, but the factors that regulate commitment to the brown adipose lineage are unknown. Here, we prospectively isolated and determined the molecular profile of embryonic brown preadipose cells. Brown adipogenic precursor activity in embryos was confined to Pdgfrα+, Myf5Cre-lineage-marked cells. RNAseq analysis identified Early B Cell Factor-2 (Ebf2) as one of the most selectively expressed genes in this cell fraction. Importantly, Ebf2-expressing cells purified from Ebf2-GFP embryos or brown fat tissue did not express myoblast or dermal cell markers and uniformly differentiated into brown adipocytes. Interestingly, Ebf2-expressing cells from white fat tissue in adult animals differentiated into brown-like (or beige) adipocytes. Loss of Ebf2 in brown preadipose cells reduced the expression levels of brown preadipose-signature genes, whereas ectopic Ebf2-expression in myoblasts activated brown preadipose-specific genes. Altogether, these results indicate that Ebf2 specifically marks and regulates the molecular profile of brown preadipose cells. Embryonic fibroblasts, isolated from dorsal body wall of E14.5 Ebf2(GFP)/+ embryos, were further fractionated based on the expression of PDGFRα and Ebf2 (GFP). Affymetrix microarray analysis was prefromed,to compare the gene expression between PDGFRα+ Ebf2(GFP)- and PDGFRα+ Ebf2(GFP)+ cells.
Project description:Brown fat dissipates energy as heat and protects against obesity. Here, we identified nuclear factor I-A (NFIA) as a novel transcriptional regulator of brown fat by a genome-wide open chromatin analysis of murine brown and white fat followed by motif analysis of brown-fat-specific open chromatin regions. NFIA and the adipogenic master regulator, PPARgamma, co-localize at the brown-fat-specific enhancers. Moreover, the binding of NFIA precedes and facilitates the binding of PPARgamma, leading to increased chromatin accessibility and active transcription. Introduction of NFIA into myoblasts results in brown adipocyte differentiation. Conversely, the brown fat of NFIA knockout mice displays impaired expression of the brown-fat-specific genes and reciprocal elevation of muscle genes. Finally, expression of NFIA and the brown-fat-specific genes is positively correlated in human brown fat. These results indicate that NFIA is a key transcriptional regulator of brown fat and exerts its effects by co-localizing with PPARg at cell-type-specific enhancers.
Project description:We performed ChIP-seq to chart genome-wide maps of H3K27me3 in brown preadipocytes and mature brown adipocytes. We observed a subset of brown fat-specific genes, but not common fat genes or white fat-specific genes, possess the H3K27me3 mark in preadipocytes, and this mark is erased in mature adipocytes.