Project description:Cyclin Dependent Kinases CDK8 and CDK19 (Mediator kinase) are regulatory components of the Mediator complex, a highly conserved complex that fine tunes transcriptional output. While Mediator kinase has been implicated in the transcriptional control of key pathways necessary for development and growth, its function in vivo has not been well described. Herein, we report the consequences of complete ablation of both Cdk8/19 on tissue homeostasis. We show that intestinal epithelial specific deletion of Mediator kinase leads to a distinct defect in secretory progenitor differentiation with broad loss of the intestinal secretory cell types. Using a phospho-proteogenomic approach, we show that the Cdk8/19 kinase module interacts with and phosphorylates components of the chromatin remodeling complex Swi/Snf in intestinal epithelial cells. Genomic localisation of Swi/Snf and Mediator shows Cdk8/19-dependent genomic binding at distinct super-enhancer loci within key lineage specification genes, including the master regulator of secretory differentiation ATOH1. Using CRISPRi/CRISPRa, we identify a distinct Mediator-Swi/Snf bound enhancer element that is necessary and sufficient for ATOH1 expression in a Mediator-kinase dependent manner. As such, these studies uncover a newly described transcriptional mechanism of ATOH1-dependent intestinal cell specification that is dependent on the coordinated interaction of the chromatin remodeling complex Swi/Snf and Mediator complex.
Project description:Cyclin Dependent Kinases CDK8 and CDK19 (Mediator kinase) are regulatory components of the Mediator complex, a highly conserved complex that fine tunes transcriptional output. While Mediator kinase has been implicated in the transcriptional control of key pathways necessary for development and growth, its function in vivo has not been well described. Herein, we report the consequences of complete ablation of both Cdk8/19 on tissue homeostasis. We show that intestinal epithelial specific deletion of Mediator kinase leads to a distinct defect in secretory progenitor differentiation with broad loss of the intestinal secretory cell types. Using a phospho-proteogenomic approach, we show that the Cdk8/19 kinase module interacts with and phosphorylates components of the chromatin remodeling complex Swi/Snf in intestinal epithelial cells. Genomic localisation of Swi/Snf and Mediator shows Cdk8/19-dependent genomic binding at distinct super-enhancer loci within key lineage specification genes, including the master regulator of secretory differentiation ATOH1. Using CRISPRi/CRISPRa, we identify a distinct Mediator- Swi/Snf bound enhancer element that is necessary and sufficient for ATOH1 expression in a Mediator-kinase dependent manner. As such, these studies uncover a newly described transcriptional mechanism of ATOH1-dependent intestinal cell specification that is dependent on the coordinated interaction of the chromatin remodeling complex Swi/Snf and Mediator complex.
Project description:We developed a compartmental model of the small intestinal epithelium that describes stem and progenitor cell proliferation and differentiation and cell migration onto the villus. The model includes a negative feedback loop from villus cells to regulate crypt proliferation and integrates heterogeneous epithelial-related processes, such as the transcriptional profile, citrulline kinetics and probability of diarrhea.
2023-09-04 | MODEL2212120003 | BioModels
Project description:Microbiota regulation of intestinal epithelial cells
Project description:The experiment goal was to identify differentially expressed proteins associated with WNT2B mutation p.R69* in human intestinal epithelia. Skin fibroblasts from a patient with the mutation were used to establish human intestinal organoids (HIOs). The hESC H1 cell line was used to generate wild-type WNT2B HIOs for comparison. The HIOs were transplanted into mice to promote maturation for 8 weeks, followed by dissection and crypt isolation to seed ex vivo epithelial (enteroid) cultures. The enteroid cultures were harvested for analysis by tandem mass tag spectrometry.