Project description:The histone variant H2A.Z is evolutionarily conserved from yeast to vertebrates. H2A.Z regulates gene expression when localized to promoter region. Recently, we identified two genes encoding H2A.Z, H2A.Z-1 and H2A.Z-2 in vertebrate genome. However, it is not clear that both H2A.Z-1 and H2A.Z-2 were required for the function of H2A.Z in gene regulation. To address this issue, we generated the H2A.Z-1 and H2A.Z-2 double knock out (KO) cells in chicken DT40 cells. The expression pattern of H2A.Z-1 and H2A.Z-2 double KO cells was compared with WT cells to characterize the genes regulated by H2A.Z-1 and H2A.Z-2. We used microarrays to analysis the alternation of gene expression between WT and H2A.Z double KO cells and identify classes of up or down regulated gene by H2A.Z-1 and H2A.Z-2. In H2A.Z-1 and H2A.Z-2 double KO cells, H2A.Z-2 is knocked out constitutively, but H2A.Z-1 conditionally by tetracycline. The expression of H2A.Z-1 transgene is suppressed completely when H2A.Z-1 and H2A.Z-2 double KO cells culture with tetracycline for three days. For this reason, we prepared the total RNA of WT cells and H2A.Z-1and H2A.Z-2 double KO cells treated with tetracycline for three days and hybridization on Affymetrix microarrays.
Project description:The histone variant H2A.Z is evolutionarily conserved from yeast to vertebrates. H2A.Z regulates gene expression when localized to promoter region. Recently, we identified two genes encoding H2A.Z, H2A.Z-1 and H2A.Z-2 in vertebrate genome. However, it is not clear that both H2A.Z-1 and H2A.Z-2 were required for the function of H2A.Z in gene regulation. To address this issue, we generated the H2A.Z-1 and H2A.Z-2 single knockout cells in chicken DT40 cells.We used microarrays to analysis the alternation of gene expression profiles in H2A.Z-1 KO and H2A.Z-2 KO cells and identify classes of up or down regulated gene by H2A.Z-1 and H2A.Z-2.
Project description:The histone variant H2A.Z plays important functions in the regulation of gene expression. In mammals, it is encoded by two genes, giving rise to two highly related isoforms named H2A.Z.1 and H2A.Z.2, which can have similar or antagonistic functions depending on the promoter. Knowledge of the physiopathological consequences of such functions emerges, but how the balance between these isoforms regulates tissue homeostasis is not fully understood. Here, we investigated the relative role of H2A.Z isoforms in intestinal epithelial homeostasis. Through genome-wide analysis of H2A.Z genomic localization in differentiating Caco-2 cells, we uncovered an enrichment of H2A.Z isoforms on the bodies of genes which are induced during enterocyte differentiation, stressing the potential importance of H2A.Z isoforms dynamics in this process. Through a combination of in vitro and in vivo experiments, we further demonstrated the two isoforms cooperate for stem and progenitor cells proliferation, as well as for secretory lineage differentiation. However, we found that they antagonistically regulate enterocyte differentiation, with H2A.Z.1 preventing terminal differentiation and H2A.Z.2 favoring it. Altogether, these data indicate that H2A.Z isoforms are critical regulators of intestine homeostasis and may provide a paradigm of how the balance between two isoforms of the same chromatin structural protein can control physiopathological processes.
Project description:The H2A.Z histone variant plays major roles in the control of gene expression. In human, H2A.Z is encoded by two genes expressing two isoforms, H2A.Z.1 and H2A.Z.2 differing by three amino acids. Here, we undertook an integrated analysis of the independent and interdependent functions of these two isoforms in gene expression using endogenously-tagged isoform. RNA-Seq analysis following depletion of either isoform or both together in untransformed cells showed that they can regulate both distinct and overlapping sets of genes positively or negatively in a context-dependent manner. Our data revealed that the two isoforms have similar or antagonistic function depending on the gene. H2A.Z.1 and H2A.Z.2 can replace each other at Transcription Start Sites, providing a molecular explanation for this interplay. Mass spectrometry analysis showed that H2A.Z.1 and H2A.Z.2 have specific interactors, PHF14 and associated proteins for H2A.Z.1 and the histone deacetylase SIRT1 for H2A.Z.2. Moreover, we show that PHF14 and SIRT1 mediate the functional antagonism between H2A.Z.1 and H2A.Z.2. In conclusion, we propose a model in which the balance between H2A.Z.1 and H2A.Z.2 at promoters is critically important to regulate specific gene expression and depends on the recruitment of specific proteins. Our work thus provides an additional layer of complexity to the control of gene expression by histone variants.
Project description:The involvement of the histone variant H2A.Z and its isoforms in the regulation of gene expression is an increasing exciting field considering the impact of such regulations in physio-pathology. Indeed, we and other recently showed that H2A.Z.1 and H2A.Z.2 isoforms exert cooperative or antagonistic transcriptional regulations on subsets of genes involved in key processes, such as proliferation, senescence or several organ functions. In this work, we analyze the relative role of both H2A.Z isoforms on parameters of the intestinal epithelial homeostasis. We observed that the amount of H2A.Z.1 and H2A.Z.2 at TSS and gene bodies are highly correlated and that the two H2A.Z isoforms can replace each other when depleted. We highlighted the role of their respective deposition onto chromatin by specific incorporators in some discrete isoform-specific contribution to the differentiation process. We have also uncovered an unexpected link between H2A.Z isoforms occupancy at gene bodies and the propensity of genes to be induced in enterocyte differentiation.
Project description:The histone variant H2A.Z is evolutionarily conserved from yeast to vertebrates. H2A.Z regulates gene expression when localized to promoter region. Recently, we identified two genes encoding H2A.Z, H2A.Z-1 and H2A.Z-2 in vertebrate genome. However, it is not clear that both H2A.Z-1 and H2A.Z-2 were required for the function of H2A.Z in gene regulation. To address this issue, we generated the H2A.Z-1 and H2A.Z-2 double knock out (KO) cells in chicken DT40 cells. The expression pattern of H2A.Z-1 and H2A.Z-2 double KO cells was compared with WT cells to characterize the genes regulated by H2A.Z-1 and H2A.Z-2. We used microarrays to analysis the alternation of gene expression between WT and H2A.Z double KO cells and identify classes of up or down regulated gene by H2A.Z-1 and H2A.Z-2.
Project description:The H2A.Z histone variant plays major roles in the control of gene expression. In human, H2A.Z is encoded by two genes expressing two isoforms, H2A.Z.1 and H2A.Z.2 differing by three amino acids. Here, we undertook an integrated analysis of the independent and interdependent functions of these two isoforms in gene expression using endogenously-tagged isoform. RNA-Seq analysis following depletion of either isoform or both together in untransformed cells showed that they can regulate both distinct and overlapping sets of genes positively or negatively in a context-dependent manner. Our data revealed that the two isoforms have similar or antagonistic function depending on the gene. H2A.Z.1 and H2A.Z.2 can replace each other at Transcription Start Sites, providing a molecular explanation for this interplay. Mass spectrometry analysis showed that H2A.Z.1 and H2A.Z.2 have specific interactors, PHF14 and associated proteins for H2A.Z.1 and the histone deacetylase SIRT1 for H2A.Z.2. Moreover, we show that PHF14 and SIRT1 mediate the functional antagonism between H2A.Z.1 and H2A.Z.2. In conclusion, we propose a model in which the balance between H2A.Z.1 and H2A.Z.2 at promoters is critically important to regulate specific gene expression and depends on the recruitment of specific proteins. Our work thus provides an additional layer of complexity to the control of gene expression by histone variants.
Project description:The H2A.Z histone variant plays major roles in the control of gene expression. In human, H2A.Z is encoded by two genes expressing two isoforms, H2A.Z.1 and H2A.Z.2 differing by three amino acids. Here, we undertook an integrated analysis of the independent and interdependent functions of these two isoforms in gene expression using endogenously-tagged isoform. RNA-Seq analysis following depletion of either isoform or both together in untransformed cells showed that they can regulate both distinct and overlapping sets of genes positively or negatively in a context-dependent manner. Our data revealed that the two isoforms have similar or antagonistic function depending on the gene. H2A.Z.1 and H2A.Z.2 can replace each other at Transcription Start Sites, providing a molecular explanation for this interplay. Mass spectrometry analysis showed that H2A.Z.1 and H2A.Z.2 have specific interactors, PHF14 and associated proteins for H2A.Z.1 and the histone deacetylase SIRT1 for H2A.Z.2. Moreover, we show that PHF14 and SIRT1 mediate the functional antagonism between H2A.Z.1 and H2A.Z.2. In conclusion, we propose a model in which the balance between H2A.Z.1 and H2A.Z.2 at promoters is critically important to regulate specific gene expression and depends on the recruitment of specific proteins. Our work thus provides an additional layer of complexity to the control of gene expression by histone variants.