Project description:The balance between pluripotency and differentiation is critical during development and regeneration. miR-203 is a microRNA previously involved in differentiation of different tissues as well as in tumor suppression in multiple malignancies. We have shown that miR-203 is able to promote differentiation of embryonic stem (ES) and induced pluripotent stem (iPS) cells without decreasing pluripotency. We have observed that transient expression of miR-203 significantly improves the efficiency of ES/iPS cells in the generation of quimeras and tetraploid complementation assays, in addition to inducing complex embryo-like structures when these pluripotent cells are injected in mice. In the present RNA seq, we intend to analyze the trascriptomic profile of miR-203 WT, KO and KI MEFs reprogrammed to inducible pluripotent cells (iPSCs) at different time points.
Project description:The balance between pluripotency and differentiation is critical during development and regeneration. miR-203 is a microRNA previously involved in differentiation of different tissues as well as in tumor suppression in multiple malignancies. We have shown that miR-203 is able to promote differentiation of embryonic stem (ES) and induced pluripotent stem (iPS) cells without decreasing pluripotency. We have observed that transient expression of miR-203 significantly improves the efficiency of ES/iPS cells in the generation of quimeras and tetraploid complementation assays, in addition to inducing complex embryo-like structures when these pluripotent cells are injected in mice. In the present RNA seq, we intend to analyze the trascriptomic profile of WT IPSCs transiently treated with DOX to induce miR-203. We analyzed the transcriptomic profile at different time points before and after the induction.
Project description:The balance between pluripotency and differentiation is critical during development and regeneration. miR-203 is a microRNA previously involved in differentiation of different tissues as well as in tumor suppression in multiple malignancies. We have shown that miR-203 is able to promote differentiation of embryonic stem (ES) and induced pluripotent stem (iPS) cells without decreasing pluripotency. We have observed that transient expression of miR-203 significantly improves the efficiency of ES/iPS cells in the generation of quimeras and tetraploid complementation assays, in addition to inducing complex embryo-like structures when these pluripotent cells are injected in mice. In the present RNA seq, we intend to analyze the trascriptomic profile of WT IPSCs, compared to miR-203 KO IPSCs and miR-203 tKI IPSCs (in which we have induced a transient over-expression of miR-203). Moreover, we analyze the mRNA profiles of the teratomas derived from those IPSCs.
Project description:The balance between pluripotency and differentiation is critical during development and regeneration. miR-203 is a microRNA previously involved in differentiation of different tissues as well as in tumor suppression in multiple malignancies. We show here that miR-203 is able to promote differentiation of embryonic stem (ES) and induced pluripotent stem (iPS) cells without decreasing pluripotency. We have observed that transient expression of miR-203 significantly improves the efficiency of ES/iPS cells in the generation of chimeras and tetraploid complementation assays, in addition to inducing complex embryo-like structures when these pluripotent cells are injected in mice. In the present RNA seq, we intend to demonstrate that transient over-expression of miR-203 make pluripotent cells (IPSCs) more similar to ES cells, also in terms of their transcriptomic profile.
Project description:Maintaining a full differentiation potential along self-renewal ability is a major property of stem cells during development and regeneration. miR-203 is a microRNA previously involved in skin differentiation and tumor suppression. We show here that transient expression of miR-203 enhances the potential of embryonic (ESC) and induced pluripotent stem cells (iPSC) in contributing to multiple lineages without decreasing their self-renewal properties. In fact, miR-203 significantly improves the efficiency of ES/iPS cells in the generation of quimeras and tetraploid complementation assays, in addition to improving the generation of complex teratomas and embryo-like structures in vivo. These effects are mediated by the direct miR-203-dependent repression of de novo DNA methyltransferases Dnmt3a and Dnmt3b, leading to genome-wide demethylation of pluripotent cells. Transient exposure to miR-203 improves functional differentiation and maturation of pluripotent cells into cardiomyocytes in a Dnmt3a/b-dependent manner, suggesting the possible therapeutic uses of this microRNA in regenerative medicine.
Project description:A hallmark of cancer cells is the metabolic switch from oxidative phosphorylation (OXPHOS) to glycolysis, a phenomenon referred to as the “Warburg effect”, which is also observed in primed human pluripotent stem cells (hPSCs). Here, we report that downregulation of SIRT2 and upregulation of SIRT1 is a molecular signature of primed hPSCs and that SIRT2 critically regulates metabolic reprogramming during induced pluripotency by targeting glycolytic enzymes including aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and enolase. Remarkably, knockdown of SIRT2 in human fibroblasts resulted in significantly decreased OXPHOS and increased glycolysis. In addition, we found that miR-200c-5p specifically targets SIRT2, downregulating its expression. Furthermore, SIRT2 overexpression in hPSCs significantly affected energy metabolism, altering stem cell functions such as pluripotent differentiation properties. Taken together, our results identify the miR-200c-SIRT2 axis as a key regulator of metabolic reprogramming (Warburg-like effect), via regulation of glycolytic enzymes, during human induced pluripotency and pluripotent stem cell function. To address our hypothesis that acetylation affects the metabolic switch, we compared protein acetylation in hESCs and hDFs by liquid chromatography-tandem mass spectrometry (LCMS/ MS) analyses following immunoprecipitation with acetyl-Lys antibody.
Project description:The balance between pluripotency and differentiation is critical during development and regeneration. miR-203 is a microRNA previously involved in differentiation of different tissues as well as in tumor suppression in multiple malignancies. We have shown that miR-203 is able to promote differentiation of embryonic stem (ES) and induced pluripotent stem (iPS) cells without decreasing pluripotency. We have observed that transient expression of miR-203 significantly improves the efficiency of ES/iPS cells in the generation of quimeras and tetraploid complementation assays, in addition to inducing complex embryo-like structures when these pluripotent cells are injected in mice. Mechanistically, we have shown that miR-203 mediates such effects, at least in part, by modulating the levels of de novo DNA methyltransferases. In the present RNAseq we have transiently silenced the levels of DNMT3a/3b in order to compare their transcriptomic profile with that observed in PSCs transiently exponed to miR-203.
Project description:Somatic cell reprogramming into pluripotent stem cells (iPSC) through the forced expression of defined factors induces changes in genome architecture reflective of the embryonic stem cell state. However, only a small minority of cells typically transition to pluripotency, which has limited our understanding of what defines cells that successfully reprogram. Here, we characterize the changes that occur across the DNA regulatory landscape during reprogramming by time-course profiling of isolated sub-populations of reprogramming intermediates poised to become iPSC. Widespread reconfiguration of chromatin states and transcription factor occupancy occurs early during reprogramming, and cells that fail to reprogram partially retain regulatory elements active in their somatic cell state. A second wave of reconfiguration occurs just prior to cells achieving pluripotency, where a majority of early changes revert to the somatic cell state and many of the changes that define the pluripotent state become established. Our comprehensive characterization of the molecular changes that occur during reprogramming broaden our understanding of the reprogramming process by providing crucial insights into iPSC generation, and shed light on how transcription factors in general access and change the chromatin during cell fate transitions.
Project description:Mouse B cells, upon ectopic expression of the transcription factor C/EBPalpha for 18h, can be reprogrammed to induced pluripotent stem (iPS) cells with extremely high efficiency. To understand the molecular control of this phenomenon we performed a time course proteomic analysis by label-free protein quantification of proteins during B cell reprogramming to iPS cells.