Inducible miRNA Expression

MicroRNA: Inducible & Reversible miRNA Expressing Mouse Models

MicroRNAs (miRNAs) are naturally occurring, post-transcriptional regulators that bind to complementary sequences in a target mRNA resulting in gene silencing. Studies suggest that over 1,000 miRNAs are present in the human genome and may target 60% of mammalian genes. Each individual miRNA may act to repress hundreds of target mRNAs. Taconic offers inducible and reversible miRNA expressing mouse models. Similar to shRNA knockdown mice, your miRNA of choice is only (over)expressed when doxycycline is administered. Withdrawal of doxycycline inhibits ectopic miRNA expression. Taconic's inducible miRNA expressing mice will be an invaluable tool to study the effect of expressing your target miRNA in vivo.
miRNA Mediated Knockdown In the absence of an inducer (doxycycline), the tet-repressor protein binds to the tet-operator control element and effectively inhibits miRNA expression from the H1 promoter. When doxycycline is administered through an animal's feed or drinking water, it binds to the tet-repressor protein and blocks its interaction with the H1 promoter. This is followed by H1 promoter activation, miRNA expression, and effective RNA mediated gene knockdown. Withdrawal of doxycycline inhibits miRNA expression resulting in pre-knockdown levels of target gene expression.
miRNA Blot Analysis Northern blot analysis demonstrates that in the absence of doxycycline, levels of specific miRNA expression in wild type and miRNA gene knockdown models are equivalent. Following one day of doxcycline administration, increased expression of miRNA in a gene knockdown model is apparent. Maximum miRNA expression is achieved following eight days administration of doxycycline. Similar levels of 5S RNA (internal standard) expression across all treatment groups indicate equal RNA loading and RNA quality.
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