These floxed mutant mice possess loxP sites flanking exon 2 of the Llgl1 gene. This strain may be useful for generating conditional mutations in applications related to the study of cell polarity.
Valeri Vasioukhin, Fred Hutchinson Cancer Research Center
The targeted Llgl1 gene encodes an evolutionarily conserved protein involved in cell polarity maintenance, and cytoskeletal structure such as apical junction complexes. Mutations in this gene have been associated with Smith-Magenis Syndrome.
These mice possess loxP sites on either side of exon 2 of the targeted 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 exon 2 deleted in the cre-expressing tissues.
Removal of the floxed sequence creates a frameshift resulting in production of only the first 27 amino acids, and a null allele.
When bred to a strain with Cre recombinase expression in early embryos (see Stock No. 003755 for example), this mutant mouse strain may be useful in studies of embryonic development of the brain, loss of cell polarity and regulation of hematopoietic stem cells.
A targeting vector containing a loxP site flanked SA-IRES beta-geo selection cassette was utilized in the construction of this mutant. This selection cassette was inserted upstream of exon 2 of the targeted gene, and another loxP site was inserted downstream of exon 2. Exon 2 is the exon downstream of the exon with the first ATG codon. This construct was electroporated into unspecified 129-derived embryonic stem (ES) cells which were transiently transfected with a Cre recombinase vector to remove the selection cassette. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were tested for germline transmission. The mice were backcrossed to C57BL/6 for 8 generations by the donating lab (see SNP notes below). Upon arrival, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).
A 48 SNP (single nucleotide polymorphism) panel analysis, with 43 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. Eleven of the 43 markers throughout the genome were segregating, suggesting an incomplete backcross.
|Allele Name||targeted mutation 1, Valeri Vasioukhin|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Llgl1, LLGL1 scribble cell polarity complex component|
|Strain of Origin||129|
|Molecular Note||The exon immediately downstream of the first coding exon was left flanked by single loxP sites following cre-mediated excision of an IRES-betageo cassette used for selection.|
When maintaining a live colony, these mice can be bred as homozygotes.
When using the Llgl1 floxed mouse strain in a publication, please cite the originating article(s) and include JAX stock #020159 in your Materials and Methods section.