STOCK Cdkn2a^{tm4(cre/ERT2)Bzsh}/J

Stock number: 039750
Product name: p16-CrexER
Research areas: Cancer Research, Neurobiology Research, Research Tools

Description

The p16-CrexER knock-in mice have Cre recombinase fused to rox-ER-rox (CrexER). The Cre recombinase activity can be induced from the endogenous cyclin dependent kinase inhibitor 2A (Cdkn2a) gene also known as p16INK4a after exposure to Dre recombinase. A fused rox-flanked ERT2 prevents nuclear translocation of Cre recombinase in the absence of tamoxifen. Upon exposure to Dre, the excision of the ERT2 sequence converts the cell to have constitutive active Cre recombinase driven by Cdkn2a. These mice are useful for intersectional genetic systems to study the roles of cellular senescence in physiological and pathological processes, including embryonic development, cancer, aging, and multiple other diseases.

Detailed description

The p16-CrexER knock-in mice have a P2A- and Cre recombinase fused to rox-ER-rox sequence inserted between the last exon and 3'UTR of the cyclin dependent kinase inhibitor 2A (Cdkn2a) gene, also known as p16INK4a. Insertion of this CrexER cassette does not affect endogenous Cdkn2a gene expression. Cdkn2a encodes a cyclin-dependent kinase (CDK) inhibitor protein expressed in senescent cell populations. The expression of p16 INK4a is essentially undetectable in young and healthy tissues, but p16 INK4a+ cells accumulate in many aged or diseased tissues. When crossed to cell/tissue-specific Dre-recombinase expressing mice, intersectional genetic tracing can be achieved in these mice. Homozygous mice are viable and fertile.

Of note, in addition to these mice, the donating investigator provided The Jackson Laboratory Repository with p16-tdT mice (Stock No. 039747), p16-CreER mice (Stock No. 039748), and p16-LSL-Dre mice (Stock No. 039749).

Development

A targeting vector containing the self-cleaving peptide 2A sequence and a complementary DNA (cDNA) encoding Cre recombinase fused to rox-ER-rox (CrexER; Cre recombinase fused to rox sequence-flanked G400V/M543A/L544A triple mutation of the human estrogen receptor ligand binding domain), followed by a woodchuck hepatitis virus post-transcriptional regulatory element (WPRE), polyA signal, and FRT-flanked neomycin resistance cassette was inserted into the last exon of the Cdkn2a gene, replacing the stop codon. The construct was electroporated into unspecified embryonic stem (ES) cells derived from a C57BL/6x129S3 genetic background. Correctly targeted ES cells were injected into blastocysts. The resulting chimeric animals were crossed to C57BL/6J, and offspring were crossed to ICR to maintain under the C57BL/6;ICR mixed background by the donating laboratory. 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 (Stock No. 000664) oocytes.

Allele

Symbol: Cdkn2a^{tm4(cre/ERT2)Bzsh}
Name: targeted mutation 4, Bin Zhou
MGI accession ID: MGI:8172894
Generation method: Targeted
Attributes: Conditional ready (e.g. floxed); Recombinase-expressing; Inducible
Marker symbol: Cdkn2a
Marker name: cyclin dependent kinase inhibitor 2A
Marker synonyms: Arf; ARF-INK4a; CAI2; CDK4I; CDKN2; CMM2; INK4; INK4A; Ink4a/Arf; INK4a-ARF; MLM; MTS1; MTS-1; P14; P14ARF; P16; p16Cdkn2a; P16INK4; P16INK4A; P19; p19^ARF; P19ARF; Pctr1; TP16
Chromosome: 4
Strain of origin: (C57BL/6 x 129S)F1
Molecular note: A targeting vector containing the self-cleaving peptide 2A sequence and a complementary DNA (cDNA) encoding Cre recombinase fused to rox-ER-rox (CrexER; Cre recombinase fused to rox sequence-flanked G400V/M543A/L544A triple mutation of the human estrogen receptor ligand binding domain) followed by a woodchuck hepatitis virus post-transcriptional regulatory element (WPRE), polyA signal, and FRT-flanked neomycin resistance cassette was inserted into the last exon of the Cdkn2a gene, replacing the stop codon.