Article

A Resource for the Conditional Ablation of microRNAs in the Mouse

UCSF Diabetes Center, UCSF, San Francisco, CA 94143, USA.
Cell Reports (Impact Factor: 8.36). 04/2012; 1(4):385-91. DOI: 10.1016/j.celrep.2012.02.008
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ABSTRACT The importance of miRNAs during development and disease processes is well established. However, most studies have been done in cells or with patient tissues, and therefore the physiological roles of miRNAs are not well understood. To unravel in vivo functions of miRNAs, we have generated conditional, reporter-tagged knockout-first mice for numerous evolutionarily conserved miRNAs. Here, we report the generation of 162 miRNA targeting vectors, 64 targeted ES cell lines, and 46 germline-transmitted miRNA knockout mice. In vivo lacZ reporter analysis in 18 lines revealed highly tissue-specific expression patterns and their miRNA expression profiling matched closely with published expression data. Most miRNA knockout mice tested were viable, supporting a mechanism by which miRNAs act redundantly with other miRNAs or other pathways. These data and collection of resources will be of value for the in vivo dissection of miRNA functions in mouse models.

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Available from: Jeffrey Bluestone, Dec 26, 2013
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    • "Procedures for the generation of miR- 200c/141 knockout mice were described previously (Park et al., 2012). Briefly, the miR-200c/141 knockout construct was generated by a previously described 'knockout-first' approach (Testa et al., 2004). "
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    • "Other research centers have established mouse clinics, with the aim of carrying out a comprehensive analysis of the phenotypes of mutant lines of specific interest (e.g., Fuchs et al., 2012; Wakana et al., 2009; Laughlin et al., 2012). The genome-wide set of targeted mutations in ES cells established by the KOMP, EUCOMM, and MirKO programs (Skarnes et al., 2011; Prosser et al., 2011; Park et al., 2012) provides an opportunity to conduct systematic, large-scale gene function analysis in a mammalian system without the variables inherent in studies by individual groups. The Sanger Institute's Mouse Genetics Project (MGP) was one of the first programs to pursue this objective, established in 2006 when the first targeted ES cells became available. "
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    • "Procedures for the generation of miR- 200c/141 knockout mice were described previously (Park et al., 2012). Briefly, the miR-200c/141 knockout construct was generated by a previously described 'knockout-first' approach (Testa et al., 2004). "
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