Project description:How the complex interaction between Mycobacterium tuberculosis (Mtb) and the host is regulated during infection is still not well understood. Using a systems biology approach, we demonstrate here that miR-155 is one of several microRNAs that regulate host gene expression over the first 48 hours of Mtb infection in macrophages. miR-155 regulates the cell survival of Mtb-infected macrophages through SHIP1/AKT signaling. Using timecourse gene expression data, we constructed a miRNA regulatory network for the innate immune response to Mtb infection by WT macrophages. The network suggested a role for seven miRNAs in regulating the host response to Mtb, with miR-155 being one of them. We then validated a role for miR-155 by comparing the response between WT and miR-155-/- macrophages.
Project description:How the complex interaction between Mycobacterium tuberculosis (Mtb) and the host is regulated during infection is still not well understood. Using a systems biology approach, we demonstrate here that miR-155 is one of several microRNAs that regulate host gene expression over the first 48 hours of Mtb infection in macrophages. miR-155 regulates the cell survival of Mtb-infected macrophages through SHIP1/AKT signaling. Using timecourse gene expression data, we constructed a miRNA regulatory network for the innate immune response to Mtb infection by WT macrophages. The network suggested a role for seven miRNAs in regulating the host response to Mtb, with miR-155 being one of them. We then validated a role for miR-155 by comparing the response between WT and miR-155-/- macrophages.
Project description:Genome-wide analysis of Jarid2, Suz12, and c-Maf binding and H3K27me3 profiling in miR-155 KO and WT Th17 performed by ChIP-seq. We found that Jarid2 and c-Maf is differentially expressed in absence of miR-155 and they compete for binding to the Il22 promoter. We highlight targets of Jarid2 and Suz12 in miR-155 KO Th17 cells that are epigenetically silenced by increased H3K27me3 status. Furthermore, genome-wide analysis through Suz12 ChIP-exo in WT and Jarid2fl/fl;CD4cre Th17 reveals defects in PRC2 recruitment in abscence of Jarid2 that results in derepression of genes in Th17 cells. Thus, one main function of miR-155 is to curb epigenetic silencing by targeting Jarid2. Examination of Jarid2, Suz12, c-Maf binding and H3K27me3 changes in miR-155 KO and WT Th17.
Project description:Genome-wide analysis of Jarid2, Suz12, and c-Maf binding and H3K27me3 profiling in miR-155 KO and WT Th17 performed by ChIP-seq. We found that Jarid2 and c-Maf is differentially expressed in absence of miR-155 and they compete for binding to the Il22 promoter. We highlight targets of Jarid2 and Suz12 in miR-155 KO Th17 cells that are epigenetically silenced by increased H3K27me3 status. Furthermore, genome-wide analysis through Suz12 ChIP-exo in WT and Jarid2fl/fl;CD4cre Th17 reveals defects in PRC2 recruitment in abscence of Jarid2 that results in derepression of genes in Th17 cells. Thus, one main function of miR-155 is to curb epigenetic silencing by targeting Jarid2.
Project description:global gene expression in caecal patch and colon of miR-155 deficient and C57BL/6 mice following infection with Citrobacter rodentium
