A Global double-fluorescent Cre reporter mouse

Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA.
genesis (Impact Factor: 2.04). 09/2007; 45(9):593-605. DOI: 10.1002/dvg.20335
Source: PubMed

ABSTRACT The Cre/loxP system has been used extensively for conditional mutagenesis in mice. Reporters of Cre activity are important for defining the spatial and temporal extent of Cre-mediated recombination. Here we describe mT/mG, a double-fluorescent Cre reporter mouse that expresses membrane-targeted tandem dimer Tomato (mT) prior to Cre-mediated excision and membrane-targeted green fluorescent protein (mG) after excision. We show that reporter expression is nearly ubiquitous, allowing visualization of fluorescent markers in live and fixed samples of all tissues examined. We further demonstrate that mG labeling is Cre-dependent, complementary to mT at single cell resolution, and distinguishable by fluorescence-activated cell sorting. Both membrane-targeted markers outline cell morphology, highlight membrane structures, and permit visualization of fine cellular processes. In addition to serving as a global Cre reporter, the mT/mG mouse may also be used as a tool for lineage tracing, transplantation studies, and analysis of cell morphology in vivo.

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Available from: Bosiljka Tasic, Sep 03, 2015
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    • "For in vivo imaging of mouse liver, surgery was performed according to a previously published procedure (Beattie et al. 2010). Briefly, 10-to 12-week-old male mt/mG (Muzumdar et al. 2007) mice were anaesthetized with ketamine ( "
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    • "Thus, to determine effects of reduced PGC-1 activity in adult b-cells while avoiding potentially confounding developmental issues, we used mice with tamoxifen-inducible b-cell-specific Cre-recombinase activity (MIP-CreERT 1Lphi ) [22]. To confirm that recombination was restricted to the islet and was tamoxifen-dependent, we introduced a double fluorescent reporter (mT/mG) [23] that expresses red fluorescent protein (tdTomato) constitutively until Cre-recombinase-mediated gene excision replaces the signal with green-fluorescent protein (GFP). In islets, no GFPþ cells were detected in mT/mG reporter mice lacking the MIP-CreERT transgene (Figure S3A). "
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