Project description:Stem cells reside in specific niches providing stemness-maintaining environments. Thus, the regulated migration from these niches is associated with differentiation onset. However, mechanisms retaining stem cells in their niche remain poorly understood. Here, we show that the epigenetic regulator lysine-specific demethylase 1 (Lsd1) organises the trophoblast niche of the early mouse embryo by coordinating migration and invasion of trophoblast stem cells (TSCs). Lsd1 deficiency leads to the depletion of the stem cell pool resulting from precocious migration of TSCs. Migration is induced by premature expression of the transcription factor Ovol2 that is repressed by Lsd1 in undifferentiated wild-type TSCs. Increasing Ovol2 levels suffices to recapitulate the migration phenotype. Furthermore, Lsd1-deficient TSCs exhibit a developmental bias towards cells of the syncytiotrophoblast and impaired spongiotrophoblast and trophoblast giant cell differentiation. In summary, we describe that the epigenetic modifier Lsd1 coordinates placental development by retaining TSCs in their niche and directing trophoblast differentiation. Mouse trophoblast stem cells (TSCs) were isoloated from a single conditional Lsd1-deficient mouse (Lsd1tm1SchM-CM-<le). Deletion of Lsd1 was induced eight days before the collection of RNA by addition of 0.2 M-BM-5M 4OH-tamoxife. Cells were isolated at successive stages of differentiation for total RNA extraction and hybridization on Affymetrix microarrays. To that end, we harvested cells at three time-points: before induction of differentiation (d0), two days after induction of differentiation (d2), and four days after induction of differentiation (d4). Three replicates (1, 2, 3) for control (-) and Lsd1-deficeint (+) cells were included for each differentiation stage.
Project description:Stem cells reside in specific niches providing stemness-maintaining environments. Thus, the regulated migration from these niches is associated with differentiation onset. However, mechanisms retaining stem cells in their niche remain poorly understood. Here, we show that the epigenetic regulator lysine-specific demethylase 1 (Lsd1) organises the trophoblast niche of the early mouse embryo by coordinating migration and invasion of trophoblast stem cells (TSCs). Lsd1 deficiency leads to the depletion of the stem cell pool resulting from precocious migration of TSCs. Migration is induced by premature expression of the transcription factor Ovol2 that is repressed by Lsd1 in undifferentiated wild-type TSCs. Increasing Ovol2 levels suffices to recapitulate the migration phenotype. Furthermore, Lsd1-deficient TSCs exhibit a developmental bias towards cells of the syncytiotrophoblast and impaired spongiotrophoblast and trophoblast giant cell differentiation. In summary, we describe that the epigenetic modifier Lsd1 coordinates placental development by retaining TSCs in their niche and directing trophoblast differentiation.
Project description:We have constituted the serum-free culture conditions (SFC) with Knockout Serum Replacement that support growth of mouse trophoblast stem cells (TSCs). The global gene expression profile of undifferentiated TSCs was maintained in the SFC. TSCs in the SFC showed differentiation potential both in vitro and in vivo.
Project description:LSD1 (also known as KDM1A) is a histone demethylase and a key regulator of gene expression in embryonic stem cells and cancer.1,2 LSD1 was initially identified as a transcriptional repressor via its demethylation of active histone H3 marks (di-methyl lysine 4 [2MK4]).1 In prostate cancer, specifically, LSD1 also co-localizes with the AR and demethylates repressive 2MK9 histone marks from androgen-responsive AR target genes, facilitating androgen-mediated induction of AR-regulated gene expression and androgen-induced proliferation in androgen-dependent cancers. We report here that the LSD1 protein is universally upregulated in human CRPC and promotes survival of CRPC cell lines. This effect is explained in part by LSD1-induced activation of cell cycle and embryonic stem cell gene setsâgene sets enriched in transcriptomal studies of lethal human tumors. Importantly, despite the fact that many of these genes are direct LSD1 targets, we did not observe histone methylation changes at the LSD1-bound regions, demonstrating non-canonical histone demethylation-independent mechanisms of gene regulation. This ChIP-seq dataset included H3K4me2 and H3K9me2 ChIP-seq data for siRNA target against LSD1 and non-targeting control, as well as SP2509 inhibition of LSD1 and mock treatment 4 conditions: siRNA against LSD1, siRNA against luciferase (non-targeting control); SP2509 inhibition of LSD1, mock treatment. There are 2 replicates per condition.
Project description:Transcription factors and chromatin modifiers play important roles in programming and reprogramming of cellular states during development. Much is known about the role of these regulators in gene activation, but relatively little is known about the critical process of enhancer silencing during differentiation. Here we show that the H3K4/K9 histone demethylase LSD1 plays an essential role in decommissioning enhancers during differentiation of embryonic stem cells (ESCs). LSD1 occupies enhancers of active genes critical for control of ESC state. However, LSD1 is not essential for maintenance of ESC identity. Instead, ESCs lacking LSD1 activity fail to fully differentiate and ESC-specific enhancers fail to undergo the histone demethylation events associated with differentiation. At enhancers, LSD1 is a component of the NuRD complex, which contains additional subunits that are necessary for ESC differentiation. We propose that the LSD1-NuRD complex decommissions enhancers of the pluripotency program upon differentiation, which is essential for complete shutdown of the ESC gene expression program and the transition to new cell states. This is the ChIP-seq part of the study.
Project description:Trophoblast stem cells (TSCs) are derived from the trophoectoderm of a blastocyst and can maintain self-renewal in vitro. Meanwhile, essential insights into the molecular mechanisms controlling placental developmental could be gained by using TSCs that can differentiate into the various placental trophoblast cell types in vitro. Esrrb is a transcription factor with pivotal roles in maintaining TSCs’ self-renewal, but the exact transcriptional networks that Esrrb involved in TSCs are largely unknown. In the present study, we elucidated the function of Esrrb during TSC self-renewal and differentiation. We demonstrate that precise levels of Essrb are critical for TSCs stemness maintenance and normal trophoblast differentiation, as Esrrb depletion results in down-regulation of the key TSC-specific transcription factors, consequently causing TSCs differentiation and forced expression of Esrrb can partially block TSCs differentiation in the absence of FGF4. This function of Esrrb is exerted by directly binding and activating a core set of TSC-specific target genes including Cdx2, Eomes, Sox2, Fgfr4 and BMP4. Furthermore, we investigate the role of Esrrb in reprogramming of mouse embryonic fibroblasts (MEFs) to induced TSCs (iTSCs). We show that Esrrb can facilitate the conversion of iTSCs from MEFs. Moreover, Esrrb can substitute for Eomes during this conversion process. Our findings provide a better understanding of the molecular mechanism of Esrrb in maintaining TSCs self-renewal and iTSCs reprogramming.
Project description:This Series reports data from a CTCF ChIP-Seq experiment performed in F1-hybrid mouse trophoblast stem cells (TSCs). The data are part of a larger study examining inactive X gene expression and chromatin states, reported as GEO Series GSE39406. Included for this dataset are FASTQ files, BED alignments and WIG files with coordinates relative to UCSC genome build mm9, and _snp files that report the location of all SNP-overlapping reads Single CTCF ChIP-Seq experiment
Project description:Although there are plenty of researches about nucleic acid in small extracellular vesicles (sEVs), properties of proteins identified as sEVs’ cargos and the mechanism of their action in recipient cell are poorly understood. Here, we show that lysine specific demethylase 1 (LSD1), the first identified histone demethylase in 2004, existed in the cell cultured medium of gastric cancer cells. Further investigation confirmed the presence of LSD1 in sEVs from gastric cancer cells and gastric cancer patient plasma, which is the first identified histone demethylase in sEVs. By shuttling from donor cells to recipient gastric cancer cells, sEVs-delivered LSD1 promoted the cancer cell stemness by positively regulating the expression of Nanog, OCT4, SOX2 and CD44, and suppressed the oxaliplatin response of the recipient cells in vitro and in vivo, while LSD1 depleted sEVs failed to suppress the oxaliplatin response. Collectively, our findings give an evidence for LSD1 as a sEVs protein to promote stemness and suppress oxaliplatin response for the first time and constitute a future avenue to predict oxaliplatin response in gastric cancer clinically.
Project description:Although there are plenty of researches about nucleic acid in small extracellular vesicles (sEVs), properties of proteins identified as sEVs’ cargos and the mechanism of their action in recipient cell are poorly understood. Here, we show that lysine specific demethylase 1 (LSD1), the first identified histone demethylase in 2004, existed in the cell cultured medium of gastric cancer cells. Further investigation confirmed the presence of LSD1 in sEVs from gastric cancer cells and gastric cancer patient plasma, which is the first identified histone demethylase in sEVs. By shuttling from donor cells to recipient gastric cancer cells, sEVs-delivered LSD1 promoted the cancer cell stemness by positively regulating the expression of Nanog, OCT4, SOX2 and CD44, and suppressed the oxaliplatin response of the recipient cells in vitro and in vivo, while LSD1 depleted sEVs failed to suppress the oxaliplatin response. Collectively, our findings give an evidence for LSD1 as a sEVs protein to promote stemness and suppress oxaliplatin response for the first time and constitute a future avenue to predict oxaliplatin response in gastric cancer clinically.