STOCK Gt(ROSA)26Sor^{tm10(ACTB-tdTomato)Luo}/J

Stock number: 017922
Product name: R26^TT
Research areas: Cell Biology Research, Neurobiology Research, Research Tools

Description

The R26^TT allele has a CMV enhancer/chicken beta-actin core promoter-driven "MADM TT" cassette inserted into the Gt(ROSA)26Sor locus on chromosome 6. These R26^TT mice exhibit widespread expression of tdTomato-3Myc (tdT3Myc) and represent the tdTomato-expressing control strain for "new MADM-6" (new mosaic analysis with double markers on chromosome 6) experiments.

Detailed description

Mice homozygous for the R26^TT allele are viable and fertile with no gross behavioral or observable abnormalities. The R26^TT allele has a CMV enhancer/chicken beta-actin core promoter-driven "MADM TT" cassette inserted into the Gt(ROSA)26Sor locus on chromosome 6. The "MADM TT" cassette has a complete tdTomato sequence (tagged with three copies of the Myc epitope at its C-terminus). As such, heterozygous and homozygous mice exhibit widespread expression of tdTomato-3Myc (direct fluorescent visualization) throughout the whole animal and all tissues.

These R26^TT mice are the tdTomato-expressing control for the "new MADM-6" (new mosaic analysis with double markers on chromosome 6) strains, including R26^GT (Stock No. 017912) and R26^TG (Stock No. 017921). These R26^TT mice do not need to be bred with any mice harboring a reciprocal mutation at the same locus to obtain tdTomato expression. A detailed description and figure showing how R26^TT mice were generated is available here.

Development

These R26^TT mice have the CMV enhancer/chicken beta-actin core promoter (pCA) upstream of the recombined "MADM TT" cassette inserted into the Gt(ROSA)26Sor locus. The recombined "MADM TT" cassette has an ATG start codon, a beta-globin intronic sequence (containing a frt-flanked region of two lox site variants [lox2272 and lox5171] followed by a single loxP site), an ATG-less tdTomato sequence (nucleotides 3-1548 including stop codon) tagged with three copies of the Myc epitope at its C-terminus, and an SV40 T-antigen poly(A) signal.

To generate these R26^TT mice, the donating investigator bred R26^GT mice (Stock No. 017912) with Hprt^Cre mice. The double mutant progeny were then bred with R26^TG mice (Stock No. 017921). The resulting triple mutant offspring (R26^GT/TG;Hprt^Cre) were next bred with wildtype mice. Cre-mediated interchromosomal recombination in meiosis resulted in mice with the R26^TT;Hprt^Cre/+ or R26^TT genotype. The resulting R26^TT animals were then bred together (and the Hprt^Cre was selectively bred out of the line) for several generations. The R26^TT mice on a mixed genetic background (mixed CD1, 129, C57BL/6 and/or FVB/N) were sent to The Jackson Laboratory Repository. Upon arrival, mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish The Jackson Laboratory Repository colony.

Allele

Symbol: Gt(ROSA)26Sor^{tm10(ACTB-tdTomato)Luo}
Name: targeted mutation 10, Liqun Luo
MGI accession ID: MGI:5314256
Generation method: Targeted
Attributes: Reporter
Marker symbol: Gt(ROSA)26Sor
Marker name: gene trap ROSA 26, Philippe Soriano
Chromosome: 6
Strain of origin: (129X1/SvJ x 129S1/Sv)F1-Kitl⁺
Expressed genes: RFP,Red Fluorescent Protein,coral; myc tag,myc tag,
Site of expression: These mice have widespread tdTomato expression when using the "new MADM-6" system.
Molecular note: Cre-mediated recombination between Gt(ROSA)26Sor^{tm6(ACTB-EGFP*,-tdTomato)Luo} and Gt(ROSA)26Sor^{tm7(ACTB-EGFP*)Luo} produces this allele. The allele has the CMV enhancer/chicken beta-actin core promoter (pCA) upstream of the recombined "MADM TT" cassette inserted into the Gt(ROSA)26Sor locus. The "MADM TT" cassette has an ATG start codon, a beta-globin intronic sequence (containing a frt-flanked region of two lox site variants [lox2272 and lox5171] followed by a single loxP site), an ATG-less tdTomato sequence (nucleotides 3-1548 including stop codon) tagged with three copies of the Myc epitope at its C-terminus, and an SV40 T-antigen poly(A) signal.