Project description:Expression profiles obtained from the villus and crypt layers of murine large intestine can elucidate the process of differentiation undergone by epithelial cells as they migrate from the undifferentiated bottom of the crypt to the villus tip before being shed into the intestinal lumen. This series includes profiles from wild type mice, as well as mice harboring mutations in genes (APC and p21) which play key roles in the differentiation process. We used microarrays to characterize gene expression profiles at the base of the crypt and at the villus tip of the lumenal layer of the large intestine in order to better understand the process of differentiation and eventual shedding undergone by cells of the large intestinal epithelium. Four wild type, four APC1638+/- and four p21-/- mice were sacrified and the large intestines dissected out. Cells from the villus tip and from the bottom of the crypt were isolated from the lumenal face of the each large intestine using the Weiser method of sequential elution. RNA was extracted from each eluted sample and used to hybridize to Affymetrix 3' expression arrays.
Project description:Expression profiles obtained from the villus and crypt layers of murine large intestine can elucidate the process of differentiation undergone by epithelial cells as they migrate from the undifferentiated bottom of the crypt to the villus tip before being shed into the intestinal lumen. This series includes profiles from wild type mice, as well as mice harboring mutations in genes (APC and p21) which play key roles in the differentiation process. We used microarrays to characterize gene expression profiles at the base of the crypt and at the villus tip of the lumenal layer of the large intestine in order to better understand the process of differentiation and eventual shedding undergone by cells of the large intestinal epithelium.
Project description:Cystic fibrosis transmembrane conductance regulator (Cftr) knockout mice present the clinical features of low body weight and intestinal disease permitting an assessment of the interrelatedness of these phenotypes in a controlled environment. To identify intestinal alterations which affect body weight in CF mice the histological phenotypes of crypt-villus axis height, goblet cell hyperplasia, and mast cell infiltrate were measured, cardiac blood samples assessed, and gene expression profiling of the ileum was completed for 12 week old (C57BL/6xBALB) F2 Cftrtm1UNC and non-CF mice presenting a range of body weight. Crypt-villus axis height decreased with increasing weight in CF, but not control, mice. Goblet cell hyperplasia and mast cell infiltration in the submucosa and muscularis externa layers of the CF intestine, were identified to be independent of bodyweight. Blood triglyceride levels were found to be significantly lower in CF mice than control mice (p = 3.02 x 10-5) but were not dependent on CF mouse body weight. By expression profiling, genes of DNA replication and lipid metabolism were among those altered in CF mice relative to non-CF controls; and no differences in gene expression were measured between samples from CF mice in the 25th and 75th percentile for weight. This study indicates that the absence of Cftr leads to altered morphology in the CF intestine the extent of which is correlated with body weight in CF mice while CF related changes in blood triglyceride levels and in the intestinal gene expression profile were not dependent on body weight in this model. Experiment Overall Design: B6xBALB F2 mice gene expression was collected for nine CF-/- mice and 6 controls. Differential expression was analyzed between the groups
Project description:Krüppel-like factor 9 (Klf9), a zinc-finger transcription factor, is implicated in the control of cell proliferation, cell differentiation and cell fate in brain and uterus. Using Klf9 null mutant mice, we have investigated the involvement of Klf9 in small intestine crypt-villus cell renewal and lineage determination. We report the predominant expression of Klf9 gene in small intestine smooth muscle (muscularis externa). Jejunums null for Klf9 have shorter villi, reduced crypt stem/transit cell proliferation, and altered lineage determination as indicated by decreased and increased numbers of Goblet and Paneth cells, respectively. A stimulatory role for Klf9 in villus cell migration was demonstrated by BrdU labeling. Results suggest that Klf9 controls the elaboration, from small intestine smooth muscle, of molecular mediator(s) of crypt cell proliferation and lineage determination, and of villus cell migration. Keywords: Genetic modification
Project description:Cystic fibrosis transmembrane conductance regulator (Cftr) knockout mice present the clinical features of low body weight and intestinal disease permitting an assessment of the interrelatedness of these phenotypes in a controlled environment. To identify intestinal alterations which affect body weight in CF mice the histological phenotypes of crypt-villus axis height, goblet cell hyperplasia, and mast cell infiltrate were measured, cardiac blood samples assessed, and gene expression profiling of the ileum was completed for 12 week old (C57BL/6xBALB) F2 Cftrtm1UNC and non-CF mice presenting a range of body weight. Crypt-villus axis height decreased with increasing weight in CF, but not control, mice. Goblet cell hyperplasia and mast cell infiltration in the submucosa and muscularis externa layers of the CF intestine, were identified to be independent of bodyweight. Blood triglyceride levels were found to be significantly lower in CF mice than control mice (p = 3.02 x 10-5) but were not dependent on CF mouse body weight. By expression profiling, genes of DNA replication and lipid metabolism were among those altered in CF mice relative to non-CF controls; and no differences in gene expression were measured between samples from CF mice in the 25th and 75th percentile for weight. This study indicates that the absence of Cftr leads to altered morphology in the CF intestine the extent of which is correlated with body weight in CF mice while CF related changes in blood triglyceride levels and in the intestinal gene expression profile were not dependent on body weight in this model. Keywords: disease state analysis
Project description:Kruppel-like factor 9 (Klf9), a zinc-finger transcription factor, is implicated in the control of cell proliferation, cell differentiation and cell fate in brain and uterus. Using Klf9 null mutant mice, we have investigated the involvement of Klf9 in small intestine crypt-villus cell renewal and lineage determination. We report the predominant expression of Klf9 gene in small intestine smooth muscle (muscularis externa). Jejunums null for Klf9 have shorter villi, reduced crypt stem/transit cell proliferation, and altered lineage determination as indicated by decreased and increased numbers of Goblet and Paneth cells, respectively. A stimulatory role for Klf9 in villus cell migration was demonstrated by BrdU labeling. Results suggest that Klf9 controls the elaboration, from small intestine smooth muscle, of molecular mediator(s) of crypt cell proliferation and lineage determination, and of villus cell migration. Experiment Overall Design: Total RNA was extracted in parallel from the jejunums of five WT and five Klf9-/- male mice (PND 30) using TRIzol reagent (Invitrogen, Carlsbad, CA). Conversion of each RNA preparation to corresponding fragmented cRNA. Fifteen ug of each cRNA was hybridized for 16 hours to an Affymetrix mouse 430A GeneChip. Ten GeneChips (each corresponding to a single animal) were hybridized, washed and scanned in parallel. Following the wash, signal amplification, and signal detection steps, GeneChips were scanned (Agilent GeneArray laser scanner) and the resultant images quantified using Affymetrix MAS 5.0 software.
Project description:Genes encoding transcription factors function as hubs in gene regulatory networks because they encode DNA-binding proteins, which bind to promoters that carry their binding sites. In the present work we have studied gene regulatory networks defined by genes with transcripts belonging to different mRNA abundance classes in the small intestinal epithelial cell. The focus is the rewiring that occurs in transcription factor hubs in these networks during the differentiation of the small intestinal epithelial cell while it migrates along the crypt-villus axis and during its development from a fetal endodermal cell to a mature adult villus epithelial cell. We have generated transcriptome data for mouse small intestinal villus, crypt and fetal intestinal epithelial cells. In addition we have generated metabolome data from crypt and villus cells. Our results show that the intestinal crypt transcription factor hubs that are rewired during differentiation are involved in the cell cycle process (E2F, NF-Y) and stem cell maintenance (c-Myc). In contrast the villi are dominated by a HNF-4 villus hub, which is rewired during differentiation by the addition of network genes with relevance for lipoprotein synthesis and lipid absorption. Moreover, we have identified a villus NF-kB hub, which was revealed by comparison of the villus and endoderm transcriptomes. The rewiring of the NF-kB villus hub during intestinal development reflects transcriptional activity established by host and microflora interactions. To aid in the mining of our results we have developed a web portal (http://gastro.imbg.ku.dk/mousecv/) allowing easy linkage between the transcriptomic data, biological processes and functions. Experiment Overall Design: Four different sample categories were analyzed. Experiment Overall Design: 1) Small intestinal crypts isolated form 12-weeks old C57BL/6 mice. These samples are in triplicates. Experiment Overall Design: 2) Small intestinal villi isolated form 12-weeks old C57BL/6 mice. These samples are in triplicates. Experiment Overall Design: 3) Embryonic day 12 mesenchyme. These samples are in quadruplicate. each sample is derived from a pool of mesenchymes (10-40) Experiment Overall Design: 4) Embryonic day 12 endoderm. These samples are in quadruplicate. each sample is derived from a pool of endoderms (10-40)
Project description:Continuously renewing tissues are often divided into proliferative and post-mitotic differentiated zones, which must retain their function also following stress and damage. Here we show how p53 operates via its two effector arms miR-34a or p21 to control enterocyte proliferation along the crypt villus axis. Whereas cell cycle is commonly regulated via the Rb pathway by CDK inhibitors, we found that in the gut epithelium, crypt cell proliferation upon p53 activation is primarily controlled by miR-34a, regulating pRb phosphorylation via the Cyclin D/CDK4 complex. Surprisingly, p21 has little effect on pRb phosphorylation and crypt cell proliferation, yet functions to secure post-mitotic villus cell quiescence via the Rb-like (RBL) /E2F4 complex, implicating distinct functions of the Rb and RBL machineries in tissue renewal. It thus appears that mammalian2tissue control of the cell cycle is far more specialized than previously appreciated, providing new opportunities to target specific tissue components for therapeutic purposes.
Project description:To assess the role of LSD1 in mouse small intestinal epithelium, we isolated small intestinal crypts and villus from wild type (WT) (Villin-Cre -; Lsd1f/f) and intestinal-epithelial-specific knock-out (cKO) (Villin-Cre+; Lsd1f/f) mice. This experiment uses a new Cre strain with 100% deletion efficiency. RNA was directly isolated from intestinal crypt and villus, and this was used for RNAseq. Gene expression analysis of cKO derived crypt and villus provides a spatially restricted outlook on the maturation status of the intestinal epithelium in the villi and the absence of Paneth cells in the crypt.
Project description:To assess the role of LSD1 in mouse small intestinal epithelium, we isolated small intestinal crypts and villus from wild type (WT) (Villin-Cre -; Lsd1f/f) and intestinal-epithelial-specific knock-out (cKO) (Villin-Cre+; Lsd1f/f) mice. This experiment uses a new Cre strain with 100% recombination efficiency. RNA was directly isolated from the crypt and villus, and this was used for RNAseq. Gene expression analysis of cKO derived crypt and villus provides a spatially restricted outlook on the maturation status of the intestinal epithelium in the villi and the absence of Paneth cells in the crypt. Additionally, these mice were treated with antibiotics to study epithelium intrinsic changes related to LSD1 deletion but independent of the bacterial microbiome.