RESUMO
For cells to exit from pluripotency and commit to a lineage, the circuitry of a core transcription factor (CTF) network must be extinguished in an orderly manner through epigenetic modifications. However, how this choreographed epigenetic remodeling at active embryonic stem cell (ESC) genes occurs during differentiation is poorly understood. In this study, we demonstrate that C-terminal binding protein 2 (Ctbp2) regulates nucleosome remodeling and deacetylation (NuRD)-mediated deacetylation of H3K27 and facilitates recruitment of polycomb repressive complex 2 (PRC2)-mediated H3K27me3 in active ESC genes for exit from pluripotency during differentiation. By genomewide analysis, we found that Ctbp2 resides in active ESC genes and co-occupies regions with ESC CTFs in undifferentiated ESCs. Furthermore, ablation of Ctbp2 effects inappropriate gene silencing in ESCs by sustaining high levels of H3K27ac and impeding H3K27me3 in active ESC genes, thereby sustaining ESC maintenance during differentiation. Thus, Ctbp2 preoccupies regions in active genes with the NuRD complex in undifferentiated ESCs that are directed toward H3K27me3 by PRC2 to induce stable silencing, which is pivotal for natural lineage commitment.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Epigênese Genética/fisiologia , Histonas/metabolismo , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Fosfoproteínas/metabolismo , Proteínas Repressoras/metabolismo , Oxirredutases do Álcool , Animais , Linhagem Celular , Montagem e Desmontagem da Cromatina/fisiologia , Proteínas Correpressoras , Proteínas de Ligação a DNA/genética , Histonas/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Nucleossomos/genética , Nucleossomos/metabolismo , Fosfoproteínas/genética , Proteínas Repressoras/genéticaRESUMO
In the title compound, C(22)H(22)ClN(3)O(4), the cyclo-hexane ring adopts a twisted half-chair conformation. The mol-ecule is stabilized by an intra-molecular O-Hâ¯N inter-action, generating an S(6) motif. The crystal packing is stabilized by inter-molecular O-Hâ¯N and C-Hâ¯O inter-actions.
RESUMO
In the title compound, C(27)H(32)N(2)O(4)S, the thio-morpholine ring adopts a chair conformation and the tetra-hydro-pyridine ring is in a distorted envelope conformation. The mol-ecular structure is stabilized by an intra-molecular O-Hâ¯O inter-action and the crystal packing is stabilized by an inter-molecular C-Hâ¯O inter-action, generating an S(6) motif and a dimer of the type R(2) (2)(18), respectively.