These floxed mutant mice possess loxP sites flanking exons 3 and 4 of the Chat gene. This strain may be useful for generating conditional mutations for studying cholinergic neurotransmission and non-neuronal cholinergic systems.
Joshua R Sanes, Harvard University
These mice possess loxP sites on either side of exons 3 and 4 of the targeted gene. Mice that are homozygous for this allele are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. When these mutant mice are bred to mice that express Cre recombinase, resulting offspring will have exons 3 and 4 deleted in the cre-expressing tissue(s). The Donating Investigator reports that the presence of the FRT site flanked PGK-Neo cassette has no detectable effect on gene expression in this strain.
When bred to a strain with Cre recombinase expression in retinal cells, this mutant mouse strain may be useful in studies of developing neural circuits in the retina.
A targeting vector containing an FRT site flanked PGK-Neo selection cassette was utilized in the construction of this mutant. This selection cassette and a loxP site was inserted 200 bp downstream of exon 4 of the targeted gene, and another loxP site was inserted 700 bp upstream of exon 3. This construct was electroporated into 129 derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts. These mice contain the FRT site flanked PGK-Neo selection cassette. The Donating Investigator reports that the presence of the FRT site flanked PGK-Neo cassette has no detectable effect on gene expression in this strain. The donating investigator reported that these mice were then bred to C57BL/6 mice for 8 generations (see SNP note below). Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) 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. Three of the 27 markers, on Chromosomes 4, 12, and 16, were found to still be segregating for 129.
|Allele Name||targeted mutation 1, Joshua R Sanes|
|Allele Type||Targeted (Conditional ready (e.g. floxed), No functional change)|
|Gene Symbol and Name||Chat, choline acetyltransferase|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||Exons 3 and 4 were floxed and an frt-flanked neo inserted into intron 4 via homologous recombination.|
|Mutations Made By|| |
Joshua Sanes, Harvard University
When maintaining a live colony, these mice can be bred as homozygotes.
When using the ChATflox mouse strain in a publication, please cite the originating article(s) and include JAX stock #016920 in your Materials and Methods section.