STOCK Tert^tm1.1Phan/J

Stock number: 030412
Product name: TERT^fl
Research areas: Cancer Research, Cell Biology Research, Research Tools

Description

TERT^fl/fl mice possess loxP sites flanking exons 1-2 of the telomerase reverse transcriptase (Tert) gene making them useful for tissue specific TERT deficiency. These floxed mice are useful when studying cancer, aging, senescence, injury/wound healing, stress, diabetes, and rare human diseases including aplastic anemia and Dyskeratosis congenita.

Detailed description

TERT^fl/fl mice possess loxP sites flanking 1.5 kb of the telomerase reverse transcriptase (Tert) promoter sequence upstream of exon 1 and exons 1-2. TERT is the catalytic component of the ribonucleoprotein complex, Telomerase. Telomerase acts by adding hexanucleotide DNA repeats, known as telomeres, which are otherwise shortened during mitosis. It is involved in cell proliferation, aging, and senescence, as well as oncogenesis, and chromosomal repair. Mice that are homozygous for this allele are viable and fertile. When bred to mice that express tissue-specific Cre recombinase, resulting offspring will have part of the promoter and exons 1-2 deleted in the cre-expressing tissues.

When bred to mice expressing tamoxifen-inducible Cre-recombinase under control of the collagen, type I, alpha 2 (Col1a2) promoter, lung fibroblasts of resulting offspring display impaired proliferation and are more susceptible to apoptosis after tamoxifen-induction.

Development

The TERT^fl/fl targeting vector was designed to insert a loxP site upstream of exon 1, including 1.5 kb of the promoter sequence, and a frt-flanked neomycin resistance (neo) cassette, followed by a second loxP site, downstream of exon 2 of the telomerase reverse transcriptase (Tert) gene. The construct was electroporated into B6(Cg)-derived Bruce4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into blastocysts and resulting chimeric mice were bred with B6.Cg-Tg(ACTFLPe)9205Dym/J transgenic mice (Stock No. 005703) to delete the neo cassette. Progeny were bred with C57BL/6NCrl mice to remove the Flp-expressing transgene. Resulting TERT^fl/fl mice were bred with C57BL/6NCrl mice for at least 5 generations. Upon arrival at The Jackson Laboratory, sperm was cryopreserved. To establish our live colony, an aliquot of frozen sperm was used to fertilize C57BL/6NJ oocytes (Stock No. 005304).

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. Two of the 43 markers throughout the genome were segregating, suggesting an incomplete backcross. Also, 3 of 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a mixed C57BL/6J ; C57BL/6N genetic background.

Allele

Symbol: Tert^tm1.1Phan
Name: targeted mutation 1.1, Sem Phan
MGI accession ID: MGI:5829569
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); No functional change
Synonyms: floxed TERT; TERT^fl
Marker symbol: Tert
Marker name: telomerase reverse transcriptase
Marker synonyms: CMM9; DKCA2; DKCB4; EST2; hEST2; hTRT; PFBMFT1; TCS1; TP2; TR; TRT
Chromosome: 13
Strain of origin: B6.Cg-Thy1^a
Molecular note: The targeting vector is designed to insert a loxP site upstream of exon 1, including 1.5 kb of the promoter sequence, and an FRT-flanked neomycin resistance cassette, followed by a second loxP site, downstream of exon 2. Flp-mediated recombination removed the FRT-flanked neo cassette leaving exons 1 and 2 floxed.