B6.129S-Trp63^{tm1.1(cre)Ssig}/J

Stock number: 024564
Product name: ΔNp63
Research areas: Developmental Biology Research, Internal/Organ Research, Research Tools

Description

The ΔNp63Cre allele expresses Cre Recombinase from the Trp63 promoter/enhancer elements in epithelial cells. These mice may be useful for genetic lineage tracing of ΔNp63-expressing cells of the caudal endoderm in vivo.

Detailed description

Heterozygous mice are viable and fertile, while homozygous mice present severe limb and skin defects and die at birth from dehydration. The ΔNp63Cre KI allele expresses Cre Recombinase from the Trp63 promoter/enhancer elements, resulting in absence of expression of ΔNp63 isoforms. ΔNp63 is expressed in basal epithelial cells and is required for normal development of the bladder and prostate glands. When these mice are bred with mice containing loxP-flanked sequence, Cre-mediated recombination will result in deletion of the floxed sequences in the Trp63-expressing cells of the offspring.

For example, when bred to B6.129X1-Gt(ROSA)26Sor^tm1(EYFP)Cos/J mice (Stock No. 006148), removal of the floxed-STOP results in enhanced yellow fluorescent protein (EYFP) expression in urogenital sinus, and all epithelial lineages of the prostate and bladder. Fluorescence was also seen in the caudal gut endoderm and the stem/progenitor compartment of adult colorectal epithelium.

Development

A targeting vector was designed to insert a Cre Recombinase gene and a frt-flanked neomycin (neo) selection cassette downstream of the transformation related protein 63 (Trp63) promoter. This results in the start codon (ATG) of the ΔNp63 transcript replacing with the start codon of Cre recombinase. This construct was electroporated into 129 Sv/Ev-derived embryonic stem (ES) cells. Correctly targeted ES cells were injected into recipient blastocysts and chimeric males were bred with C57BL/6J females. Offspring were bred with 129S4/SvJaeSor-Gt(ROSA)26Sor^tm1(FLP1)Dym/J (Stock No. 003946) mice to remove the neo cassette, and progeny were crossed to remove the Flp-expressing transgene. These ΔNp63Cre mice were bred to C57BL/6J mice for at least 5 generations. Upon arrival at The Jackson Laboratory, mice were bred with C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.

Allele

Symbol: Trp63^{tm1.1(cre)Ssig}
Name: targeted mutation 1,1, Sabina Signoretti
MGI accession ID: MGI:5502576
Generation method: Targeted
Attributes: Recombinase-expressing
Marker symbol: Trp63
Marker name: transformation related protein 63
Chromosome: 16
Strain of origin: 129S/SvEv
Expressed genes: cre,cre recombinase,bacteriophage P1
Site of expression: Cre Recombinase is expressed in epithelial cells.
Molecular note: A targeting vector was constructed with cre cDNA and an frt-flanked neomycin selection cassette flanked by Trp63 homology arms. The linearized vector was electroporated into ES cells for homologous recombination. This resulted in insertion of the ATG start codon of the cre sequence into the Trp63 locus, replacing the endogenous ATG.