COMPASS Family Histone Methyltransferase ASH2L Mediates Corticogenesis via Transcriptional Regulation of Wnt Signaling [RNA-seq]
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ABSTRACT: We show that the COMPASS family histone methyltransferase co-factor ASH2L is required in NPCs proliferation and upper layer cortical projection neurons production and position. Deletion of ASH2L impairs trimethylation of H3K4 and transcriptional machinery specifically for subsets of Wnt-β-catenin signaling, disrupting their transcription and consequently inhibiting the proliferation ability of NPCs in late stages of neurogenesis.
Project description:We show that the COMPASS family histone methyltransferase co-factor ASH2L is required in NPCs proliferation and upper layer cortical projection neurons production and position. Deletion of ASH2L impairs trimethylation of H3K4 and transcriptional machinery specifically for subsets of Wnt-β-catenin signaling, disrupting their transcription and consequently inhibiting the proliferation ability of NPCs in late stages of neurogenesis.
Project description:We show that the COMPASS family histone methyltransferase co-factor ASH2L is required in NPCs proliferation and upper layer cortical projection neurons production and position. Deletion of ASH2L impairs trimethylation of H3K4 and transcriptional machinery specifically for subsets of Wnt-β-catenin signaling, disrupting their transcription and consequently inhibiting the proliferation ability of NPCs in late stages of neurogenesis.
Project description:This SuperSeries is composed of the SubSeries listed below Histone methylation is essential for regulating gene expression during organogenesis to maintain stem cells and execute a proper differentiation program for their descendants. Here, we show that the COMPASS family histone methyltransferase co-factor ASH2L is required for maintaining neural progenitor cells (NPCs) and the production and positioning of projection neurons during neocortex development. Specifically, loss of ASH2L in NPCs results in malformation of the neocortex; the mutant neocortex shows fewer neurons that are also abnormal in composition and laminar position. Moreover, ASH2L loss impairs the trimethylation of H3K4 and the transcriptional machinery specific for Wnt-β-catenin signaling, inhibiting the proliferation ability of NPCs at late stages of neurogenesis by disrupting S phase entry to inhibit cell cycle progression. Overexpressing β-catenin after ASH2L elimination rescues the proliferation deficiency. Therefore, our findings demonstrate ASH2L is crucial for modulating Wnt signaling to maintain NPCs and generate a full complement of neurons during mammalian neocortex development.
Project description:ASH2L (Absent-Small-Homeotic-2-Like protein) is a core subunit of the COMPASS (COMplex of Proteins ASsociated with Set1) complexes, the most notable writer of the methylation of histone H3 lysine 4 (H3K4). The COMPASS complex regulates active promoters or enhancers, and its dysfunction is associated with aberrant development and disease. Here, we demonstrated that ASH2L mediated the cell invasion and migration activity of triple-negative breast cancer cells through the interaction with the COMPASS components and the target genomic regions. Transcriptome analysis indicated a potential correlation between ASH2L and the genes involved in inflammatory/immune responses. Among them, we found that the intrinsic expression of IL1B (interleukin 1 beta), an essential proinflammatory gene, was directly regulated by ASH2L. These results revealed a novel role of ASH2L on the maintenance of breast cancer malignancy possibly through H3K4 methylation of the target inflammatory/immune responsive genes.
Project description:The trithorax protein ASH2L is essential for organismal and tissue development and for cell proliferation. ASH2L is a subunit of KMT2/COMPASS methyltransferase complexes that catalyze the methylation of histone H3 lysine 4 (H3K4). Tri- and mono-methylation of H3K4 (Ash2l and H3K4me1) are associated with active promoters and enhancers, respectively. The molecular relevance of these modifications is not fully understood. We have used mouse embryo cells with a PROTAC-sensitive, degradable ASH2L to assess the functional consequences of KMT2 complex inactivation. The rapid loss of ASH2L resulted in a sequential alterations of histone marks at promoters, first a decrease of Ash2l, then an increase of H3K4me1, and a decrease of H3K27ac during the first 16 hrs, while an increase in H3K27me3 was very slow. These consequences were most prominent at CpG island promoters within a window of ±1 kb of the transcription start sites. Despite the the rapid loss of ASH2L, the effect on transcription in the first 8 hrs was minimal. This was accompanied with an alterations in gene expression and associated proliferation stop and cell cycle arrest. These findings suggest an order series of events upon loss of ASH2L that requires considerable amount of time to unfold.
Project description:To elucidate the role of H3K4 methylation in metanephros development, we selectively inactivated ASH2L, core subunit of the COMPASS complex in mice UB lineage. We then performed histone H3K4me3 modification landscape profiling of the control (Hoxb7Cre-GFP+,Ash2l F/+) and mutant (Hoxb7Cre-GFP+,Ash2l F/F) FACS-sorted UB lineage cells at E16.5 by CUT&Tag-seq.