Project description:Susceptibility to Crohn's disease, a complex inflammatory disease involving the small intestine, is controlled by over 30 loci. One Crohn's disease risk allele is in ATG16L1, a gene homologous to the essential yeast autophagy gene ATG16 (ref. 2). It is not known how ATG16L1 or autophagy contributes to intestinal biology or Crohn's disease pathogenesis. To address these questions, we generated and characterized mice that are hypomorphic for ATG16L1 protein expression, and validated conclusions on the basis of studies in these mice by analysing intestinal tissues that we collected from Crohn's disease patients carrying the Crohn's disease risk allele of ATG16L1. Here we show that ATG16L1 is a bona fide autophagy protein. Within the ileal epithelium, both ATG16L1 and a second essential autophagy protein ATG5 are selectively important for the biology of the Paneth cell, a specialized epithelial cell that functions in part by secretion of granule contents containing antimicrobial peptides and other proteins that alter the intestinal environment. ATG16L1- and ATG5-deficient Paneth cells exhibited notable abnormalities in the granule exocytosis pathway. In addition, transcriptional analysis revealed an unexpected gain of function specific to ATG16L1-deficient Paneth cells including increased expression of genes involved in peroxisome proliferator-activated receptor (PPAR) signalling and lipid metabolism, of acute phase reactants and of two adipocytokines, leptin and adiponectin, known to directly influence intestinal injury responses. Importantly, Crohn's disease patients homozygous for the ATG16L1 Crohn's disease risk allele displayed Paneth cell granule abnormalities similar to those observed in autophagy-protein-deficient mice and expressed increased levels of leptin protein. Thus, ATG16L1, and probably the process of autophagy, have a role within the intestinal epithelium of mice and Crohn's disease patients by selective effects on the cell biology and specialized regulatory properties of Paneth cells. Experiment Overall Design: 4 Samples: 2 replicates of Atg16-hypomorph Paneth cells and 2 replicates of Wildtype Paneth cells.
Project description:Susceptibility to Crohn's disease, a complex inflammatory disease involving the small intestine, is controlled by over 30 loci. One Crohn's disease risk allele is in ATG16L1, a gene homologous to the essential yeast autophagy gene ATG16 (ref. 2). It is not known how ATG16L1 or autophagy contributes to intestinal biology or Crohn's disease pathogenesis. To address these questions, we generated and characterized mice that are hypomorphic for ATG16L1 protein expression, and validated conclusions on the basis of studies in these mice by analysing intestinal tissues that we collected from Crohn's disease patients carrying the Crohn's disease risk allele of ATG16L1. Here we show that ATG16L1 is a bona fide autophagy protein. Within the ileal epithelium, both ATG16L1 and a second essential autophagy protein ATG5 are selectively important for the biology of the Paneth cell, a specialized epithelial cell that functions in part by secretion of granule contents containing antimicrobial peptides and other proteins that alter the intestinal environment. ATG16L1- and ATG5-deficient Paneth cells exhibited notable abnormalities in the granule exocytosis pathway. In addition, transcriptional analysis revealed an unexpected gain of function specific to ATG16L1-deficient Paneth cells including increased expression of genes involved in peroxisome proliferator-activated receptor (PPAR) signalling and lipid metabolism, of acute phase reactants and of two adipocytokines, leptin and adiponectin, known to directly influence intestinal injury responses. Importantly, Crohn's disease patients homozygous for the ATG16L1 Crohn's disease risk allele displayed Paneth cell granule abnormalities similar to those observed in autophagy-protein-deficient mice and expressed increased levels of leptin protein. Thus, ATG16L1, and probably the process of autophagy, have a role within the intestinal epithelium of mice and Crohn's disease patients by selective effects on the cell biology and specialized regulatory properties of Paneth cells.
Project description:In order to unravel the functional role of autophagy in skin homeostasis, we performed single-cell RNA-sequencing on total skin of 10-weeks-old male mice lacking ATG16L1 selectively in keratinocytes. Keratinocyte-specific ATG16L1 knock-out (KO) mice do not show an overt skin phenotype. By performing single-cell analysis on total skin of control mice and mice lacking ATG16L1 in keratinocytes, we could identify a crucial role for keratinocyte autophagyin mediating the timing of hair follicle stem cell activation in hair growth.
Project description:To study the epigenetic regulation of intestinal epithelium we focus on the role of chromatin modulators. Lysine-specific histone demethylase 1a (KDM1A, LSD1) is one of the enzymes that can erase the H3K4me1/2 mark. To assess the role of LSD1 in intestinal epithelium we studied wild type (WT) (Villin-Cre -; Lsd1f/f) and intestinal-epithelial-specific knock-out (KO) (Villin-Cre+; Lsd1f/f) mice. We found that KO mice completely lack Paneth cells, and have altered stem cell characteristics compared to WT littermates. To assess genome-wide H3K4me1/2 levels in WT and KO small intestines, we sorted small intestinal crypt cells, fixed them, isolated chromatin, and performed ChIP using an H3K4me1 and an H3K4me2 antibody as described in the protocols.
Project description:To study the epigenetic regulation of intestinal epithelium we focus on the role of chromatin modulators. Lysine-specific histone demethylase 1a (KDM1A, LSD1) is one of the enzymes that can erase the H3K4me1/2 mark. To assess the role of LSD1 in intestinal epithelium we studied wild type (WT) (Villin-Cre -; Lsd1f/f) and intestinal-epithelial-specific knock-out (KO) (Villin-Cre+; Lsd1f/f) mice. We found that KO mice completely lack Paneth cells, and have altered stem cell characteristics compared to WT littermates. To assess genome-wide ATAC levels in WT and KO small intestines, we isolated intestinal epithelium tissue from wild type mice and LSD1 KO mice. This tissue was digested to single cells and performed ATAC seq as described in the protocols.
Project description:A coding variant of the inflammatory bowel disease (IBD) risk gene ATG16L1 has been associated with defective autophagy and deregulation of endoplasmic reticulum (ER) function. IL-22 is a barrier protective cytokine by inducing regeneration and antimicrobial responses in the intestinal mucosa. We show that ATG16L1 critically orchestrates IL-22 signaling in the intestinal epithelium. IL-22 stimulation physiologically leads to transient ER stress and subsequent activation of STING dependent type I interferon (IFN-I) signaling, which is augmented in Atg16l1ΔIEC intestinal organoids. IFN-I signals amplify epithelial TNF production downstream of IL-22 and contribute to necroptotic cell death. In vivo, IL-22 treatment in Atg16l1ΔIEC and Atg16l1ΔIEC/Xbp1ΔIEC mice potentiates endogenous ileal inflammation and causes widespread necroptotic epithelial cell death. Therapeutic blockade of IFN-I signaling ameliorates IL-22 induced ileal inflammation in Atg16l1ΔIEC mice. Our data demonstrate an unexpected role of ATG16L1 in coordinating the outcome of IL-22 signaling in the intestinal epithelium.
Project description:To assess the role of H3K4me1 in development in mouse small intestinal epithelium, we isolated intestinal epithelium tissue from wild type mice at E18.5, P7 and P21. This tissue was digested to single cells, sorted, fixed, isolated chromatin, and performed ChIP using an H3K4me1 antibody as described in the protocols.
Project description:To assess the role of genes in development in mouse small intestinal epithelium, we isolated intestinal epithelium tissue from wild type mice at E18.5, P7 and P21. RNA was directly isolated used for RNA seq and were able to investigate gene expression at different development stages