Project description:INO80 is involved in many chromatin-dependent functions. However, its role in pluripotency has not been fully defined. We examined the impact of Ino80 deletion in the naïve and primed pluripotent stem cells. We found that Ino80 deletion had minimal effect on self-renewal and gene expression in the naïve state, but led to cellular differentiation and de-repression of developmental genes in the primed state. Mechanistically, INO80 co-occupied gene promoters that were bivalently marked by H3K4me3 and H3K27me3. Further, its occupancy was required for H3K27me3 installation and maintenance, as well as downstream gene repression. Finally, INO80 promoted H2A.Z occupancy at the bivalent domains, which in turn facilitated the polycomb repressive complex 2 (PRC2) recruitment. Together, our results identified the INO80-H2A.Z axis as an essential step for bivalent chromatin and poised gene expression and uncovered an epigenetic mechanism by which chromatin remodeling, histone variant, and histone modification coordinately control cell fate.
Project description:INO80 is involved in many chromatin-dependent functions. However, its role in pluripotency has not been fully defined. We examined the impact of Ino80 deletion in the naïve and primed pluripotent stem cells. We found that Ino80 deletion had minimal effect on self-renewal and gene expression in the naïve state, but led to cellular differentiation and de-repression of developmental genes in the primed state. Mechanistically, INO80 co-occupied gene promoters that were bivalently marked by H3K4me3 and H3K27me3. Further, its occupancy was required for H3K27me3 installation and maintenance, as well as downstream gene repression. Finally, INO80 promoted H2A.Z occupancy at the bivalent domains, which in turn facilitated the polycomb repressive complex 2 (PRC2) recruitment. Together, our results identified the INO80-H2A.Z axis as an essential step for bivalent chromatin and poised gene expression and uncovered an epigenetic mechanism by which chromatin remodeling, histone variant, and histone modification coordinately control cell fate.
Project description:INO80 is involved in many chromatin-dependent functions. However, its role in pluripotency has not been fully defined. We examined the impact of Ino80 deletion in the naïve and primed pluripotent stem cells. We found that Ino80 deletion had minimal effect on self-renewal and gene expression in the naïve state, but led to cellular differentiation and de-repression of developmental genes in the primed state. Mechanistically, INO80 co-occupied gene promoters that were bivalently marked by H3K4me3 and H3K27me3. Further, its occupancy was required for H3K27me3 installation and maintenance, as well as downstream gene repression. Finally, INO80 promoted H2A.Z occupancy at the bivalent domains, which in turn facilitated the polycomb repressive complex 2 (PRC2) recruitment. Together, our results identified the INO80-H2A.Z axis as an essential step for bivalent chromatin and poised gene expression and uncovered an epigenetic mechanism by which chromatin remodeling, histone variant, and histone modification coordinately control cell fate.
Project description:INO80 is involved in many chromatin-dependent functions. However, its role in pluripotency has not been fully defined. We examined the impact of Ino80 deletion in the naïve and primed pluripotent stem cells. We found that Ino80 deletion had minimal effect on self-renewal and gene expression in the naïve state, but led to cellular differentiation and de-repression of developmental genes in the primed state. Mechanistically, INO80 co-occupied gene promoters that were bivalently marked by H3K4me3 and H3K27me3. Further, its occupancy was required for H3K27me3 installation and maintenance, as well as downstream gene repression. Finally, INO80 promoted H2A.Z occupancy at the bivalent domains, which in turn facilitated the polycomb repressive complex 2 (PRC2) recruitment. Together, our results identified the INO80-H2A.Z axis as an essential step for bivalent chromatin and poised gene expression and uncovered an epigenetic mechanism by which chromatin remodeling, histone variant, and histone modification coordinately control cell fate.
Project description:Global regulation of H2A.Z localization by the INO80 chromatin remodeling enzyme is essential for genome integrity. Chromatin immunoprecipitation (ChIP) of Htz1 in wild-type and ino80 mutant yeast demonstrated that Ino80 plays a role in replacing Htz1 with H2A. Comparison of Htz1 localization in wt vs ino80 mutant yeast Prior to immunoprecipitation, cells arrested with alpha-factor or nocodazole: - The alpha-factor mating pheromone arrests yeast of the a mating type in the G1 phase of the cell cycle. - Nocodazole disrupts the polymerization of microtubules, blocking the cells from entering mitosis and arresting them in the G2/M phase of the cell cycle.