Mef2cflox/flox mutant mice possess loxP sites flanking the second coding exon of the myocyte enhancer factor 2C (Mef2c) gene. MEF2C is a transcription activator expressed in multiple tissues, and is involved in cell differentiation, cell survival, and apoptosis. It is specifically involved in early cardiac, vascular, and neuronal development. MEF2C is also involved in B cell survival and proliferation in response to B cell receptor stimulation. Mice that are homozygous for this allele are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have exon 2 deleted in the cre-expressing tissues.
For example, when bred to B6N.Cg-Tg(Nes-cre)1Kln/CjDswJ transgenic mice (Stock No. 019103) with Cre recombinase expression in neural progenitor cells, resulting offspring are viable but display behavioral defects.
When bred to Cd19tm1(cre)Cgn mice expressing Cre Recombinase in B cells during early development (see Stock No. 006785), resulting mice exhibit reduced immune response to antigen, defective germinal center formation, and a severe defect in B-cell proliferation via the p38 MAPK pathway.
A targeting vector was designed to insert a loxP site upstream of exon 2 and a loxP and frt-flanked neomycin resistance (neo) cassette site downstream of exon 2 of the myocyte enhancer factor 2C (Mef2c) gene. The construct was electroporated into 129S6/SvEvTac-derived W4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts and resulting chimeric mice were bred to 129S6 mice. Offspring were bred with 129S4/SvJaeSor-Gt(ROSA)26Sortm1(FLP1)Dym/J (Stock No. 003946) transgenic mice to delete the neo cassette, and progeny were crossed to remove the Flp-expressing transgene. These floxed mice were bred to FVB and C57BL/6 mice historically, and were maintained on this mixed background. Upon arrival, mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.
|Allele Name||targeted mutation 1, John J Schwarz|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Allele Synonym(s)||Mef2cflox; Mef2cloxP|
|Gene Symbol and Name||Mef2c, myocyte enhancer factor 2C|
|Strain of Origin||129S6/SvEvTac|
|Molecular Note||The targeting vector consists of a loxP site inserted upstream of exon 2, a second loxP site inserted downstream of exon 2 followed by a FRT-flanked neomycin cassette . Flp mediated recombination removed the neomycin cassette.|
When maintaining a live colony, homozygous mice may be bred together.
When using the STOCK Mef2ctm1Jjs/J mouse strain in a publication, please cite the originating article(s) and include JAX stock #025556 in your Materials and Methods section.