B6;129S4-Gt(ROSA)26Sor^{tm2(CAG-HIST1H2BB/EGFP)Zjh}/J

Stock number: 028581
Product name: HG dual
Research areas: Neurobiology Research, Research Tools

Description

These HG-dual mice harbor a targeted mutation of the Gt(ROSA)26Sor locus with a loxP-flanked STOP cassette and a frt-flanked STOP cassette preventing transcription of a CAG promoter-driven enhanced green fluorescent protein (EGFP). EGFP is only expressed following Cre-mediated and Flp-mediated recombination. This strain may be useful as an intersectional reporter for cre and FLP expression.

Detailed description

HG-dual intersectional reporter mice homozygous for this Rosa-CAG-LSL-FSF-H2B-EGFP conditional allele are viable and fertile. A loxP-flanked STOP cassette and a frt-flanked STOP cassette prevent transcription of the downstream H2B-EGFP fusion protein. Because this CAG promoter driven reporter construct was targeted for insertion into the Gt(ROSA)26Sor locus, EGFP expression is determined by which tissue(s) express Cre recombinase and, subsequently express Flp recombinase. When bred to mice that express Cre recombinase, the resulting offspring will have the loxP-flanked STOP cassette deleted in the cre-expressing tissue(s). After cre excision, expression of EGFP is restricted by the FRT-flanked STOP cassette. After removal of the two STOP cassettes by Cre- and FLP-recombination, EGFP fluorescence is expected in cells/tissues where the expression patterns of the individual promoters driving cre and Flp overlap. The donating investigator also reports that the order in which the loxP-flanked STOP and frt-flanked STOP cassettes are removed is arbitrary.

The LSL-h2b-GFP strain, B6;129S4-Gt(ROSA)26Sor^{tm8(CAG-HIST1H2BB/EGFP)Zjh}/J (Stock No. 036761) has the FRT-flanked STOP has been removed.

Development

The HG-dual targeting vector was designed with (from 5' to 3') a CMV-IE enhancer/chicken beta-actin/rabbit beta-globin hybrid promoter (CAG), a loxP-flanked STOP cassette, a frt-flanked STOP cassette, a H2B-EGFP fusion protein (coding sequence for the human HIST1H2BB gene [histone 1 H2bb] followed C-terminally by an enhanced green fluorescent protein sequence), and a Neo-polyA cassette. This entire construct was inserted between exons 1 and 2 of the Gt(ROSA)26Sor locus via electroporation of (C57BL/6 x 129S4/SvJae)F1-derived V6.5 embryonic stem (ES) cells. Correctly targeted ES cells were selected and chimeric males were bred to C57BL/6J females and offspring were subsequently bred together to create a homozygous colony of HG-dual mice. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6J oocytes (Stock No. 000664).

Allele

Symbol: Gt(ROSA)26Sor^{tm2(CAG-HIST1H2BB/EGFP)Zjh}
Name: targeted mutation 2, Z Josh Huang
MGI accession ID: MGI:5700497
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Reporter
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Chromosome: 6
Strain of origin: (C57BL/6 x 129S4/SvJae)F1
Expressed genes: H2B-eGFP,Histone H2B-enhanced Green Fluorescent Protein,
Site of expression: After Cre- and FLP-recombination, EGFP fluorescence is expected in cells/tissues where the expression patterns of the individual promoters driving Cre and Flp overlap.
Molecular note: The targeting vector is designed with (from 5' to 3') a CMV-IE enhancer/chicken beta-actin/rabbit beta-globin hybrid promoter (CAG), a loxP-flanked STOP cassette, a FRT-flanked STOP cassette, an H2B-EGFP fusion protein (coding sequence for the human HIST1H2BB gene [histone 1 H2bb] followed C-terminally by an enhanced green fluorescent protein sequence), and a Neo-polyA cassette. The entire construct was inserted between exons 1 and 2 of the Gt(ROSA)26Sor locus.