Project description:Alternative RNA splicing (AS) regulates proteome diversity, including isoform-specific expression of several pluripotency genes. Here, we integrated global gene expression and proteomic analyses and identified a molecular signature suggesting a central role for AS in maintaining human pluripotent stem cell (hPSC) self-renewal. We demonstrate the splicing factor SFRS2 is an OCT4 target gene required for pluripotency. SFRS2 regulates AS of the methyl-CpG-binding protein MBD2, whose isoforms play opposing roles in maintenance of, and reprogramming to, pluripotency. While both MDB2a and MBD2c are enriched at the OCT4 and NANOG promoters, MBD2a preferentially interacts with repressive NuRD chromatin remodeling factors and promotes hPSC differentiation, whereas overexpression of MBD2c enhances reprogramming of fibroblasts to pluripotency. The miR-301 and miR-302 families provide additional regulation by targeting SFRS2 and MDB2a. These data suggest that OCT4, SFRS2, and MBD2 participate in a positive feedback loop, regulating proteome diversity complexity in support of hPSC self-renewal and reprogramming. We isolated RNA from human fibroblasts and human embryonic stem cells for hybridization to the Affymetrix gene expression microarrays.
Project description:Using global gene expression and proteomic analyses, we identified a molecular signature in human embryonic and induced pluripotent stem cells that suggested a central regulatory role for RNA splicing in self-renewal. Through genetic and biochemical approaches, we established reciprocal functional links between the master regulatory factor OCT4 and SFRS2, a member of the serine/arginine-rich family of splicing factors. SFRS2 regulates expression of two isoforms of the methyl-CpG-binding protein MBD2 that play opposing roles in human ESC and during the reprogramming of fibroblasts. Both the MBD2a isoform expressed in fibroblasts and the MBD2c isoform found in pluripotent cells bind OCT4 and NANOG promoters in human ESC, but only MBD2a interacts with NuRD chromatin remodeling factors. Members of the miR-301 and miR-302 families provide additional regulation by targeting SFRS2 and the somatic specific MBD2a isoform. These data are consistent with a model in which OCT4, SFRS2, and MBD2 participate in a positive feedback loop to regulate proteome diversity in support of self-renewal in pluripotent cells. We isolated RNA from human iPS cells, different human fibroblasts and human embryonic stem cells for hybridization to the Affymetrix gene expression microarrays.
Project description:Alternative RNA splicing (AS) regulates proteome diversity, including isoform-specific expression of several pluripotency genes. Here, we integrated global gene expression and proteomic analyses and identified a molecular signature suggesting a central role for AS in maintaining human pluripotent stem cell (hPSC) self-renewal. We demonstrate the splicing factor SFRS2 is an OCT4 target gene required for pluripotency. SFRS2 regulates AS of the methyl-CpG-binding protein MBD2, whose isoforms play opposing roles in maintenance of, and reprogramming to, pluripotency. While both MDB2a and MBD2c are enriched at the OCT4 and NANOG promoters, MBD2a preferentially interacts with repressive NuRD chromatin remodeling factors and promotes hPSC differentiation, whereas overexpression of MBD2c enhances reprogramming of fibroblasts to pluripotency. The miR-301 and miR-302 families provide additional regulation by targeting SFRS2 and MDB2a. These data suggest that OCT4, SFRS2, and MBD2 participate in a positive feedback loop, regulating proteome diversity complexity in support of hPSC self-renewal and reprogramming.
Project description:Using global gene expression and proteomic analyses, we identified a molecular signature in human embryonic and induced pluripotent stem cells that suggested a central regulatory role for RNA splicing in self-renewal. Through genetic and biochemical approaches, we established reciprocal functional links between the master regulatory factor OCT4 and SFRS2, a member of the serine/arginine-rich family of splicing factors. SFRS2 regulates expression of two isoforms of the methyl-CpG-binding protein MBD2 that play opposing roles in human ESC and during the reprogramming of fibroblasts. Both the MBD2a isoform expressed in fibroblasts and the MBD2c isoform found in pluripotent cells bind OCT4 and NANOG promoters in human ESC, but only MBD2a interacts with NuRD chromatin remodeling factors. Members of the miR-301 and miR-302 families provide additional regulation by targeting SFRS2 and the somatic specific MBD2a isoform. These data are consistent with a model in which OCT4, SFRS2, and MBD2 participate in a positive feedback loop to regulate proteome diversity in support of self-renewal in pluripotent cells.