These Fsp27 floxed mutant mice possess loxP sites flanking exons 2 and 3 of the Cidec gene. This strain may be useful for generating conditional mutations in applications related to the regulation of fat storage in adipocytes.
Frank J Gonzalez, National Institutes of Health (NIH/NCI)
The Cidec gene, also known as Fsp27, fat-specific protein 27, encodes a protein that binds to lipids, promoting adipocyte lipid droplet formation, and is involved in adipocyte apoptosis. These mice possess loxP sites flanking exons 2 and 3 of the targeted Cidec gene. Mice that are homozygous for this allele are viable and fertile. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 2 and 3 deleted in the cre-expressing tissues. During backcrossing, the Y chromosome may not have been fixed to the C57BL/6N genetic background.
When bred to a strain with Cre recombinase expression in adipocytes (see Stock No. 005069 for example), this mutant mouse strain may be useful in studies of lipid homeostasis and fat storage in adipocytes.
A FRT site-flanked targeting vector containing a NEO selection cassette was utilized in the construction of this mutant. This selection cassette with a 5’ loxP site was inserted downstream of exon 3 of the targeted gene, and another loxP site was inserted upstream of exon 2. This construct was electroporated into (C57BL/6J x 129S4/SvJae)F1 derived-v6.4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6N blastocysts. The resulting chimeric mice were crossed with wild-type C57BL/6N mice. The mice were further crossed to beta-actin driven FLP transgenic mouse line (on an unknown genetic background) to remove the NEO selection cassette.
The mice were then backcrossed to C57BL/6N for 10 generations.
During backcrossing, the Y chromosome may not have been fixed to the C57BL/6N genetic background.
Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6NJ (Stock No. 005304) at least once to establish the colony.
A 32 SNP (single nucleotide polymorphism) panel analysis, with 27 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the rederived living colony at The Jackson Laboratory Repository. Two of the 27 markers throughout the genome were segregating, one was likely associated with the targeted mutation on Chromosome 6. Also, 2 of 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J ; C57BL/6N genetic background.
|Allele Name||targeted mutation 1.1, Frank Gonzalez|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Cidec, cell death-inducing DFFA-like effector c|
|Strain of Origin||(C57BL/6J x 129S4/SvJae)F1|
|Molecular Note||The targeting vector contains a loxP site upstream of exon 2 and an FRT-flanked neomycin selection cassette followed by a second loxP site downstream of exon 3. Flp-mediated recombination removed the FRT-flanked neo cassette leaving exons 2 and 3 floxed.|
When maintaining a live colony, these mice can be bred as homozygotes.
When using the Fsp27 flox mouse strain in a publication, please cite the originating article(s) and include JAX stock #027284 in your Materials and Methods section.