Project description:The development and severity of inflammatory bowel diseases (IBD) and other chronic inflammatory conditions can be influenced by host genetic and environmental factors, including signals derived from commensal bacteria. However, the mechanisms that integrate these diverse cues remain undefined. Here we demonstrate that intestinal epithelial cells (IECs) isolated from IBD patients exhibit decreased expression of the epigenome-modifying enzyme histone deacetylase 3 (HDAC3). Further, genome-wide analyses of murine IECs that lack HDAC3 (HDAC3ΔIEC) revealed that HDAC3 deficiency resulted in dysregulated gene expression coupled with alterations in histone acetylation. Critically, conventionally-housed HDAC3ΔIEC mice demonstrated loss of Paneth cells, impaired IEC function and alterations in the composition of intestinal commensal bacteria. In addition, HDAC3ΔIEC mice exhibited significantly increased susceptibility to intestinal damage and inflammation, indicating that epithelial expression of HDAC3 plays a central role in maintaining intestinal homeostasis. Strikingly, rederivation of HDAC3ΔIEC mice into germ-free conditions revealed that dysregulated IEC gene expression, Paneth cell homeostasis, and intestinal barrier function were largely restored in the absence of commensal bacteria. Collectively, these data indicate that the HDAC3 is a critical factor that integrates commensal bacteria-derived signals to calibrate epithelial cell responses required to establish normal host-commensal relationships and maintain intestinal homeostasis. Analyses of histone acetylation in primary IECs from HDAC3FF (3 biologic replicates) and HDAC3ΔIEC (3 biologic replicates) mice were conducted utilizing ChIP-seq for H3K9Ac.
Project description:The development and severity of inflammatory bowel diseases (IBD) and other chronic inflammatory conditions can be influenced by host genetic and environmental factors, including signals derived from commensal bacteria. However, the mechanisms that integrate these diverse cues remain undefined. Here we demonstrate that intestinal epithelial cells (IECs) isolated from IBD patients exhibit decreased expression of the epigenome-modifying enzyme histone deacetylase 3 (HDAC3). Further, genome-wide analyses of murine IECs that lack HDAC3 (HDAC3?IEC) revealed that HDAC3 deficiency resulted in dysregulated gene expression coupled with alterations in histone acetylation. Critically, conventionally-housed HDAC3?IEC mice demonstrated loss of Paneth cells, impaired IEC function and alterations in the composition of intestinal commensal bacteria. In addition, HDAC3?IEC mice exhibited significantly increased susceptibility to intestinal damage and inflammation, indicating that epithelial expression of HDAC3 plays a central role in maintaining intestinal homeostasis. Strikingly, rederivation of HDAC3?IEC mice into germ-free conditions revealed that dysregulated IEC gene expression, Paneth cell homeostasis, and intestinal barrier function were largely restored in the absence of commensal bacteria. Collectively, these data indicate that the HDAC3 is a critical factor that integrates commensal bacteria-derived signals to calibrate epithelial cell responses required to establish normal host-commensal relationships and maintain intestinal homeostasis. In this study, we performed gene expression profiling to examine how the transcriptional profiles in primary live, EpCAM+ IECs from the large intestine differed between control HDAC3FF mice (3 biological replicates) and IEC-intrinsic knockout HDAC3?IEC mice (3 biological replicates).
Project description:The development and severity of inflammatory bowel diseases (IBD) and other chronic inflammatory conditions can be influenced by host genetic and environmental factors, including signals derived from commensal bacteria. However, the mechanisms that integrate these diverse cues remain undefined. Here we demonstrate that intestinal epithelial cells (IECs) isolated from IBD patients exhibit decreased expression of the epigenome-modifying enzyme histone deacetylase 3 (HDAC3). Further, genome-wide analyses of murine IECs that lack HDAC3 (HDAC3ΔIEC) revealed that HDAC3 deficiency resulted in dysregulated gene expression coupled with alterations in histone acetylation. Critically, conventionally-housed HDAC3ΔIEC mice demonstrated loss of Paneth cells, impaired IEC function and alterations in the composition of intestinal commensal bacteria. In addition, HDAC3ΔIEC mice exhibited significantly increased susceptibility to intestinal damage and inflammation, indicating that epithelial expression of HDAC3 plays a central role in maintaining intestinal homeostasis. Strikingly, rederivation of HDAC3ΔIEC mice into germ-free conditions revealed that dysregulated IEC gene expression, Paneth cell homeostasis, and intestinal barrier function were largely restored in the absence of commensal bacteria. Collectively, these data indicate that the HDAC3 is a critical factor that integrates commensal bacteria-derived signals to calibrate epithelial cell responses required to establish normal host-commensal relationships and maintain intestinal homeostasis. In this study, we performed gene expression profiling to examine how the transcriptional profiles in primary live, EpCAM+ IECs from the large intestine differed between germ-free control HDAC3FF mice (3 biological replicates) and germ-free IEC-intrinsic knockout HDAC3ΔIEC mice (3 biological replicates).
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other