Project description:We used transcriptomics to investigate how Mucispirillum schaedleri ASF 457 interferes with the gene expression of Salmonella Typhimurium in the cecum of gnotobiotic mice
Project description:Mucispirillum schaedleri is an abundant inhabitant of the intestinal mucus layer of rodents and other animals. To gain insights into its lifestyle, we analyzed the genome and transcriptome of M. schaedleri ASF 457 and tested for traits predicted by the genome using physiological experiments. Although thought to be a mucus degrader, its genome surprisingly predicts that M. schaedleri has limited capacity for degrading host-derived mucosal glycans or other complex polysaccharides. Rather, it may utilize small compounds such as peptides, amino acids, glycerol, and short chain fatty acids. Additionally, it can reduce nitrate and has systems for scavenging oxygen and reactive oxygen species, which accounts for its presence close to the mucosal tissue and during inflammation. Also of note, M. schaedleri harbors a type VI secretion system (T6SS) and several putative effector proteins containing eukaryotic domains, which suggest intimate interactions with the host and a role in inflammation. Examination of the individual phylogenies of all genes in the M. schaedleri genome revealed extensive horizontal gene transfer, primarily from intestinal Epsilon- and Deltaproteobacteria. Though M. schaedleri utilizes non-horizontally-transferred pathways (e.g. nitrate reduction), horizontally-acquired pathways from gut organisms (e.g. T6SS and glycerol-P utilization) are also likely also important for its survival in the intestine, suggesting that lateral gene transfer may have played a key role in facilitating its establishment in the gut ecosystem.
Project description:Background: MicroRNAs (miRNAs) acting as negative regulators of gene expression are differentially expressed in intestinal tissues of patients with inflammatory bowel disease (IBD). Assessing the functional role of miRNAs in murine models of colitis facilitates elucidating the role of specific miRNAs in human IBD. The aim of this study was to determine the miRNA signature of murine models of colitis and to assess the influence of miR-21 on intestinal inflammation. Methods: miRNAs expression was accessed by microarray for acute and chronic murine model of colitis induced by DSS or TNBS. miR-21-deficient mouse and littermates controls were assessed in the standard DSS, TNBS and CD4+ T cell transfer models of colitis. RNAs of mouse colon and CD4+CD45RBHigh cells were analyzed by miRNA and mRNA microarray, and quantitative RT-PCR. Th1 polarization was accessed by flow-cytometry and ELISA. Results: Alterations of in miRNAs expression were identified for acute and chronic DSS colitis and TNBS colitis, receptively. The Expression of miRs-21, -142-3p and -223 was were distinct between DSS and TNBS models while overlap of numerous miRNAs was seen. Importantly, miRs-19b, -192 and -215, that are decreased in IBD, were significantly decreased in all 4 models of colitis. miR-21, which is increased in IBD, was increased in TNBS colitis but not the DSS colitis models. Further assessment of the miR-21-deficient 1-/- mice revealed that the deletion of miR-21 results in the exacerbation of both the TNBS and T cell-transfer models of colitis. Conclusions: miRNAs are differentially expressed in both human IBD and murine colitis, with overlap of several IBD-associated miRNAs. The demonstration that miR-21 deletion exacerbated CD4+ T cell-mediated models of colitis provides further evidence that miRNAs play significant roles in the pathogenesis of IBD. miRNAs expression was accesed for acute and chronic murine model of colitis induced by DSS or TNBS.Total of 20 samples with duplicates were analyed in this study.
Project description:Background: MicroRNAs (miRNAs) acting as negative regulators of gene expression are differentially expressed in intestinal tissues of patients with inflammatory bowel disease (IBD). Assessing the functional role of miRNAs in murine models of colitis facilitates elucidating the role of specific miRNAs in human IBD. The aim of this study was to determine the miRNA signature of murine models of colitis and to assess the influence of miR-21 on intestinal inflammation. Methods: miRNAs expression was accessed by microarray for acute and chronic murine model of colitis induced by DSS or TNBS. miR-21-deficient mouse and littermates controls were assessed in the standard DSS, TNBS and CD4+ T cell transfer models of colitis. RNAs of mouse colon and CD4+CD45RBHigh cells were analyzed by miRNA and mRNA microarray, and quantitative RT-PCR. Th1 polarization was accessed by flow-cytometry and ELISA. Results: Alterations of in miRNAs expression were identified for acute and chronic DSS colitis and TNBS colitis, receptively. The Expression of miRs-21, -142-3p and -223 was were distinct between DSS and TNBS models while overlap of numerous miRNAs was seen. Importantly, miRs-19b, -192 and -215, that are decreased in IBD, were significantly decreased in all 4 models of colitis. miR-21, which is increased in IBD, was increased in TNBS colitis but not the DSS colitis models. Further assessment of the miR-21-deficient 1-/- mice revealed that the deletion of miR-21 results in the exacerbation of both the TNBS and T cell-transfer models of colitis. Conclusions: miRNAs are differentially expressed in both human IBD and murine colitis, with overlap of several IBD-associated miRNAs. The demonstration that miR-21 deletion exacerbated CD4+ T cell-mediated models of colitis provides further evidence that miRNAs play significant roles in the pathogenesis of IBD. miRNAs expression was accesed for acute and chronic murine model of colitis induced by DSS or TNBS.Total of 20 samples with duplicates were analyed in this study.
Project description:Background: MicroRNAs (miRNAs) acting as negative regulators of gene expression are differentially expressed in intestinal tissues of patients with inflammatory bowel disease (IBD). Assessing the functional role of miRNAs in murine models of colitis facilitates elucidating the role of specific miRNAs in human IBD. The aim of this study was to determine the miRNA signature of murine models of colitis and to assess the influence of miR-21 on intestinal inflammation. Methods: miRNAs expression was accessed by microarray for acute and chronic murine model of colitis induced by DSS or TNBS. miR-21-deficient mouse and littermates controls were assessed in the standard DSS, TNBS and CD4+ T cell transfer models of colitis. RNAs of mouse colon and CD4+CD45RBHigh cells were analyzed by miRNA and mRNA microarray, and quantitative RT-PCR. Th1 polarization was accessed by flow-cytometry and ELISA. Results: Alterations of in miRNAs expression were identified for acute and chronic DSS colitis and TNBS colitis, receptively. The Expression of miRs-21, -142-3p and -223 was were distinct between DSS and TNBS models while overlap of numerous miRNAs was seen. Importantly, miRs-19b, -192 and -215, that are decreased in IBD, were significantly decreased in all 4 models of colitis. miR-21, which is increased in IBD, was increased in TNBS colitis but not the DSS colitis models. Further assessment of the miR-21-deficient 1-/- mice revealed that the deletion of miR-21 results in the exacerbation of both the TNBS and T cell-transfer models of colitis. Conclusions: miRNAs are differentially expressed in both human IBD and murine colitis, with overlap of several IBD-associated miRNAs. The demonstration that miR-21 deletion exacerbated CD4+ T cell-mediated models of colitis provides further evidence that miRNAs play significant roles in the pathogenesis of IBD. Gene expression profiles were established for normal miR-21-/- mice and wild type c57BL/6 mice (WT). Total of 6 samples with replicates were included in this study.