Project description:We have generated a miR-17~92 transgene and fl/fl allele whose expression can be turned on and off conditionally by Cre recombinase. The mice were crossed to CD19-Cre mice to turn on and off the expression of miR-17~92 specifically in B cells and stimulated LPS/IL-4 for 25.5hr. tKO mice were generated in the miR-106a-363-/-;miR-106b-25-/- background, so that all three homologous cluster of miR-17~92 family miRNAs are deleted in B cells.
Project description:We have generated a miR-17-92 transgenic allele (termed miR-17-92 Tg) whose expression can be turned on conditionally by Cre recombinase (Xiao et al, Nature Immunology, 9:405-14, 2008). The mice were crossed to CD19-Cre mice to turn on the transgene expression specifically in B cells. Follicular B(FoB) cells were purified from CD19-Cre;miR-17~92 Tg/Tg mice (FoBtg1, FoBtg2, FoBtg3) and miR-17~92 Tg/Tg mice (FoBwt1, FoBwt2, FoBwt3) by MACS depletion of cells positive for CD5, CD43, and CD93 (also known as AA4.1). The purity of follicular B cells was examined by flow cytometry and was greater than 95% for all samples. Total RNA was extracted using RNeasy kit (QIAGEN).
Project description:We have generated a miR-17-92 transgenic allele (termed miR-17-92 Tg) whose expression can be turned on conditionally by Cre recombinase (Xiao et al, Nature Immunology, 9:405-14, 2008). The mice were crossed to CD19-Cre mice to turn on the transgene expression specifically in B cells. Follicular B(FoB) cells were purified from CD19-Cre;miR-17~92 Tg/Tg mice (TG1, TG2, TG3) and miR-17~92 Tg/Tg mice (WT1, WT2, WT3) by MACS depletion of cells positive for CD5, CD43, and CD93 (also known as AA4.1). The purified B cells were stimulated with LPS/IL-4 for 13.5hr or 25.5hr. The purity of follicular B cells was examined by flow cytometry and was greater than 95% for all samples. Total RNA was extracted using RNeasy kit (QIAGEN).
Project description:We have generated a miR-17-92 transgenic allele (termed miR-17-92 Tg) whose expression can be turned on conditionally by Cre recombinase (Xiao et al, Nature Immunology, 9:405-14, 2008). The mice were crossed to CD19-Cre mice to turn on the transgene expression specifically in B cells.
Project description:We have generated a miR-17-92 transgenic allele (termed miR-17-92 Tg) whose expression can be turned on conditionally by Cre recombinase (Xiao et al, Nature Immunology, 9:405-14, 2008). The mice were crossed to CD19-Cre mice to turn on the transgene expression specifically in B cells.
Project description:miR-17 from the miR-17-92 cluster regulate activation-induced cell death in T cells and modulate inducible regulatory T cell differentiation. We used microarrays to detail the global program of gene expression modulated by miR-17 and aim to identify the potential targets of miR-17. CD4 T cells from wild type or miR-17-92 deficient mice were activated and transduced with empty vector or that overexpressing miR-17. Potential targets of miR-17 should be upregulated in miR-17-92 deficient CD4 T cells compared to wild type CD4 T cells, and downregulated when miR-17 were reintroduced into the miR-17-92 deficient T cells.
Project description:Knockout of the ubiquitously expressed microRNA-17~92 cluster in mice produces a lethal developmental defect and blocked B lymphopoiesis. We validated the equally widely expressed Bcl2l11 gene as joint target of miR-17~92 cluster members. Bcl2l11 encodes the pro-apoptotic protein BIM, central to life-death decisions in most mammalian cells. To study the contribution of miR-17~92:Bim interaction to miR-17~92 overall function, we set up a system of conditional mutagenesis of the Bim 3’UTR in mice. Ago2 Photoactivatable-Ribonucleoside Cross-linking and Immunoprecipitation (AGO2 PAR-CLIP) allowed us to assess whether the seed match mutations introduced into the Bim 3’UTR in vivo indeed precluded interaction with the miRNAs of the 17~92 cluster. This analysis was done in Abelson Virus transformed B cell progenitors which we generated from wild type and Bim3’UTRmut/mut E14.5 fetal livers, knowing that these cells express both BIM and miR-17~92, can be expanded to large numbers and incorporate 4-thiouridine sufficiently well. Focusing on 21 nt windows around the 9 putative miR-17~92 seed matches in the Bim 3’UTR and excluding reads lacking T-to-C transitions, we we verified that the introduced mutationsare functional, and we discovered differential seed match coverage in the wild type, with one miR-19 seed match co-dominating with two miR-92 seed matches, while in the mutant 3’UTR miR-17~92 binding was completely abolished. These results demonstrate functionality and efficiency of our genetically engineered mouse model for in vivo conditional seed-match inactivation. These results demonstrate functionality and efficiency of our genetically engineered mouse model for in vivo conditional seed-match inactivation.