Isolation and Cultivation of Naive-Like Human Pluripotent Stem Cells Based on HERVH Expression Investigators describe a protocol for genetic and phenotypic tagging, selecting and maintaining naive-like human pluripotent stem cells. [Nat Protoc] Abstract | Press Release H2A.Z.1 Monoubiquitylation Antagonizes BRD2 to Maintain Poised Chromatin in ESCs Scientists investigated the function of H2A.Z.1 monoubiquitylation by mutation of the PRC1 target residues (H2A.Z.1K3R3). They showed that H2A.Z.1K3R3 is properly incorporated at target promoters in murine embryonic stem cells, but loss of monoubiquitylation leads to de-repression of bivalent genes, loss of Polycomb binding, and faulty lineage commitment. [Cell Rep] Full Article | Graphical Abstract Serum-Based Culture Conditions Provoke Gene Expression Variability in Mouse Embryonic Stem Cells as Revealed by Single-Cell Analysis Researchers performed single-cell mRNA-seq analysis of mouse embryonic stem cells (ESCs) and uncovered significant heterogeneity in ESCs cultured in serum. They defined highly variable gene clusters with distinct chromatin states and show that bivalent genes are prone to expression variation. [Cell Rep] Full Article | Graphical Abstract Genetic Variation, Not Cell Type of Origin, Underlies the Majority of Identifiable Regulatory Differences in iPSCs The authors found a remarkably small number of differences in DNA methylation and gene expression levels between induced pluripotent stem cells (iPSCs) derived from different somatic precursors. They demonstrated genetic variation is associated with the majority of identifiable variation in DNA methylation and gene expression levels. [PLoS Genet] Full Article Precision Medicine: Genetic Repair of Retinitis Pigmentosa in Patient-Derived Stem Cells Scientists tested whether CRISPR/Cas9 could be used in patient-specific induced pluripotent stem cells to precisely repair an RPGR point mutation that causes X-linked retinitis pigmentosa. [Sci Rep] Full Article | Press Release GSK3β Inhibition Promotes Efficient Myeloid and Lymphoid Hematopoiesis from Non-human Primate-Induced Pluripotent Stem Cells Scientists generated transgene-free induced pluripotent stem cells (iPSCs) from different non-human primate species and showed the efficient induction of mesoderm, myeloid, and lymphoid cells from these iPSCs using a GSK3β inhibitor. [Stem Cell Reports] Full Article | Graphical Abstract NANOG Binds to GLI Proteins and Represses Hedgehog-Mediated Transcription To study the transcriptional response of stem cells to Hedgehog (HH) signaling, investigators searched for proteins binding to GLI proteins, the transcriptional effectors of the HH pathway in mouse embryonic stem (ES) cells. They found that both GLI3 and GLI1 bind to the pluripotency factor NANOG. [J Biol Chem] Abstract | Full Article Embryonic Stem Cells Exhibit mRNA Isoform Specific Translational Regulation Researchers investigated the differential translation rates of individual mRNA variants in embryonic stem cells (ESCs) and in ESC derived Neural Precursor Cells using polysome profiling coupled to RNA sequencing. [PLoS One] Full Article Cytoskeletal Expression and Remodeling in Pluripotent Stem Cells Mouse embryonic stem cells and reprogrammed induced pluripotent stem cells, as well as the original un-reprogrammed embryonic fibroblasts, were evaluated for expression of cytoskeletal markers. Scientists found that pluripotent stem cells overall have a less developed cytoskeleton compared to fibroblasts. [PLoS One] Full Article |