Project description:Human pluripotent stem cells have two major pluripotent states, primed and naive, and the heterogeneity among cell lines in each pluripotent state remains a major unresolved problem. We showed that the overexpression of H1FOO-DD, which has a short expression period by fusing the destabilized domain to the maternal-specific linker histone H1FOO, together with OCT4, SOX2, KLF4 and LMYC in human somatic cells improves the quality of reprogramming to primed and naive pluripotency.
Project description:Naive and primed human pluripotent stem cells (hPSC) provide valuable models to study cellular and molecular developmental processes. The lack of detailed information about cell-surface protein expression in these two pluripotent cell types prevents an understanding of how the cells communicate and interact with their microenvironments. Here, we used plasma membrane profiling to directly measure cell-surface protein expression in naive and primed hPSC. This unbiased approach quantified over 1700 plasma membrane proteins including those involved in cell adhesion, signalling and cell interactions. Notably, multiple cytokine receptors upstream of JAK-STAT signalling were more abundant in naive hPSC. In addition, functional experiments showed that FOLR1 and SUSD2 proteins are highly expressed at the cell surface in naive hPSC but are not required to establish human naive pluripotency. This study provides a comprehensive stem cell proteomic resource that uncovers differences in signalling pathway activity and has identified new markers to define human pluripotent states.
Project description:Human pluripotent cell lines were derived from blastocyst-stage embryos and propagated in self-renewal conditions that maintain features of naive pluripotency characteristic of mouse embryonic stem cells. Genome-wide DNA methylation status of HNES1 and HNES3 naive and primed cells was assessed with post-bisulfite adapter tagging (PBAT).
Project description:We introduce a method for generating transgene-free and high-quality naive human induced pluripotent stem cells (iPSCs) using a modified Sendai virus (SeV) vector reprogramming system. This reprogramming method realizes the derivation of naive iPSCs from various somatic cells accompanied with fast and robust SeV vector removal at early passages. The established naive iPSCs have superior naive-specific differentiation ability compared with iPSCs derived from conventional methods.
Project description:Naive pluripotent epiblast cells of the preimplantation murine embryo and their in vitro counterpart, embryonic stem (ES) cells, have the capacity to give rise to all cells of the adult. Such developmental plasticity is associated with global genome hypomethylation. It is unclear whether genome methylation is dynamically regulated only via differential expression of DNA methyltransferases (DNMTs) and Ten-eleven Translocation (TET) enzymes, which oxidase methylated DNA. Here we show that LIF/Stat3 signalling induces genomic hypomethylation via metabolic reconfiguration. In Stat3-/- ES cells we observed decreased alpha-ketoglutarate (ɑKG) production from reductive Glutamine metabolism, leading to decreased TET activity, increased Dnmt3a/b expression and to a global increase in DNA methylation. Notably, genome methylation is dynamically controlled by simply modulating αKG availability, mitochondrial activity or Stat3 activation in mitochondria, indicating effective crosstalk between metabolism and the epigenome. Stat3-/- ES cells also show increased methylation at Imprinting Control Regions accompanied with differential expression of >50% of imprinted genes. Single-cell transcriptome analysis of Stat3-/- embryos confirmed dysregulated expression of Dnmt3a/b, Tet2, and imprinted genes in vivo. Our results reveal that the LIF/Stat3 signal bridges the metabolic and epigenetic profiles of naive pluripotent cells, ultimately controlling genome methylation and imprinted gene expression. Several imprinted genes regulate cell proliferation and are often misregulated in tumors. Moreover, a wide range of cancers display Stat3-overactivation, raising the possibility that the molecular module we described here is exploited under pathological conditions.
Project description:Human naive pluripotent stem cells have unrestricted lineage potential. Underpinning this property, naive cells are thought to lack chromatin-based lineage barriers. However, this assumption has not been tested. Here, we apply multi-omics to comprehensively define the chromatin-associated proteome, histone post-translational modifications and transcriptome of human naive and primed pluripotent stem cells. Integrating the chromatin-bound proteome and histone modification data sets reveals differences in the relative abundance and activities of distinct chromatin modules, identifying a strong enrichment of Polycomb Repressive Complex 2 (PRC2)-associated H3K27me3 in naive pluripotent stem cell chromatin. Single-cell approaches and human blastoid models reveal that PRC2 activity acts as a chromatin barrier restricting the differentiation of naive cells towards the trophoblast lineage, and inhibiting PRC2 promotes trophoblast fate induction and cavity formation. Our results establish that human naive pluripotent stem cells are not epigenetically unrestricted, but instead possess chromatin mechanisms that oppose the induction of alternative cell fates.
Project description:Significant interest has been devoted to the isolation of human pluripotent stem cells displaying the naive state of mouse embryonic stem cells. However, to what extent naive human cells isolated in culture resemble pluripotent cells in vivo remains unclear. Here we present three lines of evidence indicating that naive pluripotent stem cells generated in the absence of transgenes share defining molecular signatures with the human pre-implantation embryo. First, a comprehensive analysis of the transposcriptome reveals that naive human cells have a retroelement expression profile of human cleavage stage embryos. Second, base-resolution mapping of the DNA methylome in naive human cells reveals a genome-wide reduction in CpG and non-CpG methylation levels. Third, female naive cells exhibit an X chromosome status that is similar to that of the human blastocyst. Our work demonstrates that pluripotent stem cells with epigenomic hallmarks of the early human embryo can be directly captured in vitro. Examine the methylomes of 6 naïve, 2 primed and 2 re-primed human embryonic stem cells