Project description:This SuperSeries is composed of the following subset Series: GSE37262: A Nuclear Receptor Coactivator is Essential for Esrrb Activity and the Induction and Maintenance of the ES Cell State GSE40192: Global gene expression analysis of Ncoa3 knockdown in mouse embryonic stem cells Refer to individual Series
Project description:Lipid metabolism is recognized as a key process for stem cell maintenance and differentiation but genetic factors that instruct stem cell function by influencing lipid metabolism remain to be delineated. Here we identify Tnfaip2 as an inhibitor of reprogramming of mouse fibroblasts into induced pluripotent stem cells. Tnfaip2 knockout embryonic stem cells (ESCs) exhibit differentiation failure and knockdown of the planarian orthologue, Smed-exoc3, abrogates in vivo differentiation of somatic stem cells, tissue homeostasis, and regeneration. Tnfaip2 deficient ESCs fail to induce synthesis of cellular triacylglycerol (TAG) and lipid droplets (LD) coinciding with reduced expression of Vimentin (Vim) – a known inducer of LD formation. Knockdown of Vim and Tnfaip2 act epistatically in enhancing cellular reprogramming of mouse fibroblasts. Similarly, planarians devoid of Smed-exoc3 displayed acute loss of TAGs. Supplementation of palmitic acid (PA) and palmitoyl-L-carnitine (a mitochondrial carrier of PA) restores the differentiation capacity of Tnfaip2 deficient ESCs as well as stem cell differentiation and organ maintenance in Smed-exoc3-depleted planarians. Together, these results identify a novel pathway, which is essential for stem cell differentiation and organ maintenance by instructing lipid metabolism.
Project description:Lipid metabolism is recognized as a key process for stem cell maintenance and differentiation but genetic factors that instruct stem cell function by influencing lipid metabolism remain to be delineated. Here we identify Tnfaip2 as an inhibitor of reprogramming of mouse fibroblasts into induced pluripotent stem cells. Tnfaip2 knockout embryonic stem cells (ESCs) exhibit differentiation failure and knockdown of the planarian orthologue, Smed-exoc3, abrogates in vivo differentiation of somatic stem cells, tissue homeostasis, and regeneration. Tnfaip2 deficient ESCs fail to induce synthesis of cellular triacylglycerol (TAG) and lipid droplets (LD) coinciding with reduced expression of Vimentin (Vim) – a known inducer of LD formation. Knockdown of Vim and Tnfaip2 act epistatically in enhancing cellular reprogramming of mouse fibroblasts. Similarly, planarians devoid of Smed-exoc3 displayed acute loss of TAGs. Supplementation of palmitic acid (PA) and palmitoyl-L-carnitine (a mitochondrial carrier of PA) restores the differentiation capacity of Tnfaip2 deficient ESCs as well as stem cell differentiation and organ maintenance in Smed-exoc3-depleted planarians. Together, these results identify a novel pathway, which is essential for stem cell differentiation and organ maintenance by instructing lipid metabolism.
Project description:Orphan nuclear receptor Esrrb is vital in maintaining ES cells and like Oct4, Sox2 and Nanog is essential for self-renewal and pluripotency. Esrrb functions in somatic cells via LBD/AF-2-dependent coactivator recruitment to target genes. Here we show that in ES cells coactivator recruitment is similarly required and identify Ncoa3 as the Esrrb coactivator needed for activation of its target genes. Ncoa3 is essential for self-renewal and the induction of pluripotency in reprogramming, and genome-wide analysis of Ncoa3 binding reveals extensive overlap with Esrrb and pluripotency factors along with marks of active genes. Mechanistically, we show Ncoa3 is specifically required to bridge RNApol2 to Esrrb. We thus identify a new member of the ES pluripotency network and describe Esrrb and Ncoa3 as key factors linking core pluripotency factors to the general transcription machinery. Three biological replicates each for control scrambled shRNA and Ncoa3 shRNA transfected E14 mouse ESCs. The global gene expression profiles of Ncoa3 knockdown cells were compared to control scrambled shRNA knockdown cells 4 days post-transfection.