These mice contain loxP sites on either side of exon 23 of the targeted gene. Mice homozygous for this "Dicer-flox" allele are viable and fertile and exhibit no gross phenotypic or behavioral abnormalities. Expression of the targeted allele is indistinguishable from wildtype despite the presence of an frt-flanked neomycin cassette between exon 23 and the 3' loxP site. Cre-mediated recombination (resulting in deletion of exon 23) in the germline leads to developmental arrest at embryonic day 7.5 (E7.5). Tissue specific deletion results in the loss of microRNA (miRNA) processing. Mutant mice can be used to generate cell/tissue-specific deletions of the endogenous gene for applications in embryonic development, translation, protein processing and miRNA/siRNA regulation of gene expression.
For example, when crossed to a strain expressing Cre recombinase in mesenchyme (see Stock No. 005584), this mutant mouse strain may be useful in studies of limb morphogenesis.
When bred to a strain expressing Cre recombinase in the neural tube (see Stock No. 009107 for example), this mutant mouse strain may be useful in studies of DiGeorge syndrome, miRNA biogenesis and neural crest cell development.
When bred to a strain expressing Cre recombinase in the distal posterior region of E10-E12 embryos (see Stock No. 005622 for example), this mutant mouse strain may be useful in studies of lung epithelial morphogenesis.
When bred to a strain expressing Cre recombinase in Foxp3+ cells from the lymph nodes, spleen and thymus (see Stock No. 014579 for example), this mutant mouse strain may be useful in studies miRNA and the function of T reg cells.
When bred to a strain expressing Cre recombinase in Foxp3+ regulatory T cells (Foxp3tm4(YFP/cre)Ayr; see Stock No. 016959 for example), this mutant mouse strain may be useful in studies inflammation and the function of T reg cells.
