STOCK Gt(ROSA)26Sor^tm1(DTA)Jpmb/J

Stock number: 006331
Product name: ROSA26^eGFP-DTA
Research areas: Cell Biology Research, Neurobiology Research, Research Tools

Description

ROSA26-eGFP-DTA mice have a loxP-flanked STOP cassette preventing expression of diphtheria toxin fragment A (DTA). Exposure to Cre recombinase removes the lox-stop fragment - resulting in ablation of the cre-expressing cells. These ROSA26-eGFP-DTA mice are useful for Cre-inducible deletion of specific groups of cells.

C57BL/6J-congenic ROSA26-eGFP-DTA mice are available as Stock No. 032087.

Detailed description

The ROSA26-eGFP-DTA allele has a loxP-flanked STOP sequence (EGFP::PGK-neo::3xpolyA) upstream of the diphtheria toxin A subunit (DTA) gene. Mutant mice display widespread expression of EGFP, but DTA transcription is prevented by the strong transcriptional stop sequence. When bred to mice that express Cre recombinase under the control of a promoter of interest, the floxed-STOP cassette is removed and DTA expression is activated - resulting in the specific ablation of the cre-expressing cells. Homozygous mice are viable, normal in size, and do not display any gross physical or behavioral abnormalities. The donating investigator reports that some homozygous males are subfertile.

ROSA26-eGFP-DTA mice may be useful on their own as a fluorescent reporter, or in combination with cre-expressing mice to produce conditional deletions of specific groups of cells. ROSA26-eGFP-DTA mice may also have applications in toxicology and protein synthesis research.

For example, when crossed to a strain expressing Cre recombinase in the midbrain and dorsal spinal cord (see Stock No. 007807 or 009107), DTA expression is activated resulting in elimination of the cre-expressing cells, this mutant mouse strain may be useful in studies of midbrain and neural tube development.

For example, when crossed to a strain expressing tamoxifen-inducible Cre recombinase in keratinocytes (see Stock No. 005107), DTA expression is activated resulting in alterations in the location and morphology of KRT7 expressing cells and may be useful in studies of acid reflux.

C57BL/6J-congenic ROSA26-eGFP-DTA mice are available as Stock No. 032087.

Development

A targeting vector was designed placing a loxP-flanked Enhanced Green Fluorescent Protein (EGFP, Clontech), PGK-Neo cassette, and a triple SV40 polyadenylation signal fragment upstream of the diphtheria toxin A subunit (DTA). This construct was inserted into the Gt(ROSA)26Sor locus via electroporation into 129S6/SvEvTac-derived CCE embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts. Chimeric males were bred to C57BL/6J females. The resulting heterozygotes were bred to CD1 mice for 2-3 generations and then made homozygous prior to arrival at The Jackson Laboratory.

Allele

Symbol: Gt(ROSA)26Sor^tm1(DTA)Jpmb
Name: targeted mutation 1, Juan Pedro Martinez-Barbera
MGI accession ID: MGI:3610389
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Reporter; Inserted expressed sequence
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Chromosome: 6
Strain of origin: 129S/SvEv-Gpi1^c
Expressed genes: GFP,Green Fluorescent Protein,; Dta,Diphtheria toxin A chain,
Site of expression: Expression of EGFP is widespread. When bred to Cre recombinase expressing mice, the loxP-flanked EGFP and stop sequence are removed, and DTA expression is activated, resulting in the specific ablation of cre-expressing cells.
Molecular note: A targeting vector contained a conditionally expressed DTA construct downstream of a floxed DNA region containing EGFP, a neo cassette and a triple SV40. An EGFP is upstream of the DTA and is constitutively expressed under the control of the ROSA26 protmoter.
General note: The time lapse between onset of Cre expression and cell death is estimated to be less than 24 hours.