Project description:Here we performed a ChIP-seq experiment on a sample of adherent cultures of mouse neural stem cells (NS5 cell line) under normal growth conditions and upon short term activation (30 minutes) of an inducible version of the proneural factor Mash1/Ascl1 (Ascl1-ERT2). This resulted in the generation of a genome-wide map of Ascl1 binding to chromatin.
Project description:FOXO transcription factors are central regulators of longevity from worms to humans. FOXO3 – the FOXO isoform associated with exceptional human longevity – preserves adult neural stem cell pools. Here we identify FOXO3 direct targets genome-wide in primary cultures of adult neural progenitor cells (NPCs). Interestingly, FOXO3-bound sites are enriched for motifs for bHLH transcription factors and FOXO3 shares common targets with the pro-neuronal bHLH transcription factor ASCL1/MASH1 in NPCs. Analysis of the chromatin landscape reveals that FOXO3 and ASCL1 are particularly enriched at the enhancers of genes involved in neurogenic pathways. Intriguingly, FOXO3 inhibits ASCL1-dependent neurogenesis in NPCs and direct neuronal conversion in fibroblasts. FOXO3 also restrains neurogenesis in vivo. Our study identifies a genome-wide interaction between the pro-longevity transcription factor FOXO3 and the cell fate determinant ASCL1, and raises the possibility that FOXO3’s ability to restrain ASCL1-dependent neurogenesis may help preserve the neural stem cell pool. ChIP-seq profiles of two transcription factors (FOXO3 and ASCL1) and three histone marks (H3K4me1, H3K4me3 and H3K27me3) in adult mouse neural progenitor cells.
Project description:Primary human astrocytes were infected with either monkeypox virus (MPXV clade IIb lineage), vaccinia virus (VACV: Acambis 2000), or controls (MC=monkeypox control, AC = Vaccinia control) at an MOI of 10 for 6 h. Samples (n=4) were analyzed by LC-MS/MS with label-free quantification where the data was acquired by data-dependent acquisition (DDA).
Project description:Neuroblastoma is an embryonic malignancy originating from early nerve cells. Neuroblastoma retains plasticity, interconverting between the mesenchymal (MES) and adrenergic (ADRN) states, which are controlled by different sets of transcription factors forming the core regulatory circuit (CRC). However, their functional roles and cooperative mechanisms in neuroblastoma pathogenesis are poorly understood. Here, we demonstrate that overexpression of ASCL1 in MES neuroblastoma cells opens closed chromatin at the promoters of key ADRN genes, accompanied by epigenetic activation and establishment of enhancer-promoter interactions, thereby initiating subtype switching. ASCL1 inhibits the TGFb-SMAD2/3 pathway but activates the BMP-SMAD1-ID3/4 pathway, serving as negative feedback to balance the function of ASCL1-TCF12 dimers. ASCL1 and other ADRN CRC members potentiate each other’s activity, increasing the expression of the original targets and inducing a new set of genes, thereby promoting conversion to ADRN neuroblastoma. Thus, via its pioneer factor function, ASCL1 serves as a master regulator that characterizes ADRN neuroblastoma.
Project description:To identify the downstream targets of transcription factor Ascl1, transcriptional profiling of rat glial cell line, CG4 cell, transfected with either Ascl1 or mock control was performed. Comparison was performed between Ascl1 overexpressing CG4 cell and mock control transduced cell on 3D-Gene rat mRNA oligo 12k chip. Biological replication was not prepared. The results were confirmed by real time RT-PCR in several genes.
Project description:NCI-H1618 cells treated on d0 and d3 with 25 nM control or ASCL1-targeting siRNA. Biologic triplicate RNA samples harvested at day 5.
Project description:Here we performed a ChIP-seq experiment on a sample of adherent cultures of mouse neural stem cells (NS5 cell line) expressing an inducible version of the proneural factor Mash1/Ascl1 (Ascl1-ERT2) under normal growth conditions and after 24 hours of activation by 4-Hydroxytamoxifen. This resulted in the generation of a genome-wide map of histone modifications H3K27ac and H3K4me1.
Project description:To elucidate whether or not a subtype of adenocarcinoma with neuroendocrine nature has poor prognosis, we performed gene expression profiling of an achaete-scute complex homolog 1 (ASCL1) siRNA experiment. siRNA againt ASCL1 was transfected into DMS79 cells.
Project description:ChIP-seq analysis was performed in an neuroblastoma cell line to analyze DNA bindings of H3K27ac in GI-MEN DOX-ASCL1 cells and ASCL1-HA in GI-MEN DOX-ASCL1-tag-HA cells.