STOCK Gt(ROSA)26Sor^{tm1(CAG-Dmrt1,-EGFP)Zark}/J

Stock number: 035789
Product name: CAG-Stop-Dmrt1-Gfp
Research areas: Cancer Research, Research Tools

Description

CAG-Stop-Dmrt1-Gfp knock-in mice conditionally express Dmrt1 (doublesex and mab-3 related transcription factor 1) and an EGFP reporter. This strain may be useful for studying vertebrate sex determination.

Detailed description

Dmrt1 (doublesex and mab-3 related transcription factor 1) encodes a key gene in mammalian testis differentiation. These conditional CAG-Stop-Dmrt1-Gfp mice contain from 5' to 3', a CAG promoter, a floxed STOP (neomycin (neo) resistance gene), the mouse Dmrt1 coding sequence and an FRT-flanked IRES-EGFP inserted into the Gt(ROSA)26Sor locus. Mice that are homozygous for the targeted insertion are viable and fertile. In the absence of cre, gene expression is prevented by the STOP cassette. After removal of the loxP-flanked neo cassette via Cre-mediated recombination, Dmrt1 and EGFP are expressed. EFGP expression can be eliminated following a cross to a mouse carrying a flp recombinase. Post-cre expression of Dmrt1 is comparable to wildtype. DMRT1 is expressed in both sexes until about E13.5, after E13.5 expression is testes specific.

For example, when bred to mice with widespread Cre recombinase expression (Tg(UBC-cre/ERT2)1Ejb, such as Stock No. 007001), ovaries from female progeny express SOX9+ Sertoli-like cells suggesting that the transdifferentiation of granulosa cells has occurred.

Development

The targeting vector contains a CAG promoter followed by a loxP-STOP-loxP (containing a Pgk-Neo in reverse orientation), human beta-globin (HBB) 5' UTR, mouse Dmrt1 coding sequence, an FRT-flanked IRES-EGFP and a triple polyA inserted downstream of exon of the ROSA26 locus. The construct was electroporated into 129S1/Sv-derived CJ7 embryonic stem (ES) cells. The resulting chimeric animals were crossed to C57BL/6J and offspring were intercrossed to generate a homozygous colony by the donating laboratory (see SNP note below). Upon arrival, mice were bred to C57BL/6J for at least 1 generation to establish the colony.

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. One of the 43 markers throughout the genome were segregating with an unknown source. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed genetic background.

Allele

Symbol: Gt(ROSA)26Sor^{tm1(CAG-Dmrt1,-EGFP)Zark}
Name: targeted mutation 1, David Zarkower
MGI accession ID: MGI:6471079
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Reporter; Inserted expressed sequence
Synonyms: CAG-Stop-Dmrt1-Gfp
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Marker synonyms: beta geo; Gtrgeo26; Gtrosa26; R26; ROSA26; SETD5-AS1; Thumpd3as1
Chromosome: 6
Strain of origin: 129S1/Sv-Oca2⁺ Tyr⁺ Kitl⁺
Site of expression: The CAG promoter allows a widespread pattern of expression.
Molecular note: The targeting vector contains a CAG promoter followed by a loxP-STOP-loxP (containing a Pgk-Neo in reverse orientation), human beta-globin (HBB) 5'; UTR, mouse Dmrt1 coding sequence, an FRT-flanked IRES-EGFP and a triple polyA inserted downstream of exon of the ROSA26 locus.