The Polycomb group (PcG) gene products mediate heritable silencing of developmental regulators in metazoans, participating in one of two distinct multimeric protein complexes, the Polycomb repressive complexes-1 (PRC1) and -2 (PRC2). PRC2 catalyses trimethylation of histone H3 at lysine 27 (H3K27) which in turn is thought to provide a recruitment site for PRC1. Recent studies demonstrate that mono-ubiquitylation of histone H2A at lysine 119 is important in PcG mediated silencing with the core PRC1 component Ring1A/B functioning as the E3 ligase8. PRC2 has been shown to share target genes with the core transcription network to maintain embryonic stem (ES) cells including Oct4 and Nanog. Here we identify an essential role for PRC1 in repressing developmental regulators in ES cells, and thereby in maintaining ES cell pluripotency. A significant proportion of the PRC1 target genes are also repressed by Oct4. We demonstrate that engagement of PRC1 and PRC2 at target genes is Oct4-dependent and moreover that Ring1B interacts with Oct4. Collectively these results show that PcG complexes are instrumental in Oct4-dependent repression required to maintain pluripotency of ES cells. This study provides a first functional link between a core ES cell regulator and global epigenetic regulation of the genome.
Polycomb group proteins Ring1A/B are functionally linked to the core transcriptional regulatory circuitry to maintain ES cell identity.
No sample metadata fields
View SamplesThe Polycomb group (PcG) gene products mediate heritable silencing of developmental regulators in metazoans, participating in one of two distinct multimeric protein complexes, the Polycomb repressive complexes-1 (PRC1) and -2 (PRC2)1-5. PRC2 catalyses trimethylation of histone H3 at lysine 27 (H3K27) which in turn is thought to provide a recruitment site for PRC13-7. Recent studies demonstrate that mono-ubiquitylation of histone H2A at lysine 119 is important in PcG mediated silencing with the core PRC1 component Ring1A/B functioning as the E3 ligase8. PRC2 has been shown to share target genes with the core transcription network to maintain embryonic stem (ES) cells including Oct4 and Nanog9. Here we identify an essential role for PRC1 in repressing developmental regulators in ES cells, and thereby in maintaining ES cell pluripotency. A significant proportion of the PRC1 target genes are also repressed by Oct4. We demonstrate that engagement of PRC1 and PRC2 at target genes is Oct4-dependent and moreover that Ring1B interacts with Oct4. Collectively these results show that PcG complexes are instrumental in Oct4-dependent repression required to maintain pluripotency of ES cells. This study provides a first functional link between a core ES cell regulator and global epigenetic regulation of the genome.
Polycomb group proteins Ring1A/B are functionally linked to the core transcriptional regulatory circuitry to maintain ES cell identity.
No sample metadata fields
View SamplesThe Polycomb group (PcG) gene products mediate heritable silencing of developmental regulators in metazoans, participating in one of two distinct multimeric protein complexes, the Polycomb repressive complexes-1 (PRC1) and -2 (PRC2)1-5. PRC2 catalyses trimethylation of histone H3 at lysine 27 (H3K27) which in turn is thought to provide a recruitment site for PRC13-7. Recent studies demonstrate that mono-ubiquitylation of histone H2A at lysine 119 is important in PcG mediated silencing with the core PRC1 component Ring1A/B functioning as the E3 ligase8. PRC2 has been shown to share target genes with the core transcription network to maintain embryonic stem (ES) cells including Oct4 and Nanog9. Here we identify an essential role for PRC1 in repressing developmental regulators in ES cells, and thereby in maintaining ES cell pluripotency. A significant proportion of the PRC1 target genes are also repressed by Oct4. We demonstrate that engagement of PRC1 and PRC2 at target genes is Oct4-dependent and moreover that Ring1B interacts with Oct4. Collectively these results show that PcG complexes are instrumental in Oct4-dependent repression required to maintain pluripotency of ES cells. This study provides a first functional link between a core ES cell regulator and global epigenetic regulation of the genome.
Polycomb group proteins Ring1A/B are functionally linked to the core transcriptional regulatory circuitry to maintain ES cell identity.
No sample metadata fields
View SamplesTwo distinct Polycomb complexes, PRC1 and PRC2, collaborate to maintain epigenetic repression of key developmental loci in embryonic stem cells (ESCs). PRC1 and PRC2 have histone modifying activities, catalyzing mono-ubiquitination of histone H2A (H2AK119u1) and trimethylation of H3 lysine 27 (H3K27me3) respectively. Compared to H3K27me3, localization and role of H2AK119ub1 is not fully understood in ESCs. Here we present genome-wide H2AK119u1 maps in ESCs and identify a group of genes at which H2AK119u1 is deposited in a Ring1-dependent manner. These genes are a distinctive subset of genes with H3K27me3 enrichment and are the central targets of Polycomb silencing that are required to maintain ESC identity. We further show that the H2A ubiquitination activity of PRC1 is dispensable for its target binding and its activity to compact chromatin at Hox loci, but is indispensable for efficient repression of target genes and thereby ESC maintenance. These data demonstrate that multiple effector mechanisms including H2A ubiquitination and chromatin compaction combine to mediate PRC1-dependent repression of genes that are crucial for the maintenance of ESC identity. Utilization of these diverse effector mechanisms might provide a means to maintain a repressive state that is robust yet highly responsive to developmental cues during ES cell self-renewal and differentiation.
Histone H2A mono-ubiquitination is a crucial step to mediate PRC1-dependent repression of developmental genes to maintain ES cell identity.
Specimen part, Cell line, Treatment
View SamplesWe used microarrays to investigate the restoration of repression of PRC1 target gene expression in Ring1A/B-dKO ES cells stably expressing either of mock, WT or mutant Ring1B construct.
Histone H2A mono-ubiquitination is a crucial step to mediate PRC1-dependent repression of developmental genes to maintain ES cell identity.
Specimen part, Treatment
View SamplesExpression data of ES cells with or without Pcgf6, Ring1A/B, Max and Mga. Expression data of ES cells with or without Cbx1/3. Overall design: Mouse embryonic stem cells deficient for Pcgf6 and associating genes were evaluated using RNA-seq. Mouse embryonic stem cells deficient for Cbx1/3 and associating genes were evaluated using RNA-seq.
PCGF6-PRC1 suppresses premature differentiation of mouse embryonic stem cells by regulating germ cell-related genes.
Specimen part, Cell line, Treatment, Subject, Time
View SamplesPolycomb repressive complexes (PRCs) are important chromatin regulators of ES cell function. RYBP binds Polycomb H2A monoubiquitin ligases Ring1A and Ring1B, and has been suggested to participate in localizing Polycomb complexes to their targets. Moreover, constitutive inactivation of RYBP precludes ES cell formation. Here we have used ES cells conditionally deficient in RYBP to investigate RYBP function. Chromosome immunoprecipitation on a chip (ChIP-chip) of RYBP and microarray experiments were performed using wild type and knocked-out ES cells.
RYBP represses endogenous retroviruses and preimplantation- and germ line-specific genes in mouse embryonic stem cells.
Specimen part, Disease
View SamplesWe used microarrays to investigate a global change in gene expression by conditional depletion of Rybp in mouse ES cells.
RYBP represses endogenous retroviruses and preimplantation- and germ line-specific genes in mouse embryonic stem cells.
Specimen part
View SamplesGene expression change by Yaf2 KD in wild type or RYBP KO ES cells.
RYBP represses endogenous retroviruses and preimplantation- and germ line-specific genes in mouse embryonic stem cells.
Specimen part
View SamplesTranscriptomes of differentiated cells of the conditionally immortalized mouse podocyte cell line SVI (Schiwek et al., Kidney Int. 66: 91-101, 2004) were determined as described in Warsow et al. (Kidney Int. 84: 104-115, 2013) after application of mechanical stress (Endlich et al., J. Am. Soc. Nephrol. 12: 413-422, 2001) as compared to control conditions.
Mechanical stress enhances CD9 expression in cultured podocytes.
Specimen part, Cell line
View Samples