B6;129-Trp53^tm2Holl/J

Stock number: 008045
Research areas: Apoptosis Research, Cancer Research, Immunology, Inflammation and Autoimmunity Research, Research Tools

Description

In this mutant strain, the sequence of the endogenous mouse gene (exons 4-9) has been replaced with the homologous human TRP53 region including sequence encoding proline at codon 72 (human polymorphic site). Immortalized cell lines derived from primary embryonic fibroblasts harvested from these mice frequently harbor a TRP53 (p53) mutation in the DNA binding domain typical of those found in human tumors. This mutant mouse strain may be useful in studies related to spontaneous and induced mutation of the human TRP53 gene in human cancers, and for testing pharmacological agents in vivo for their activity in altering DNA-binding activity of mutant TRP53 proteins found in tumors.

Detailed description

In this mutant strain, exons 4-9 of the endogenous mouse Trp53 gene have been replaced with the homologous human TRP53 region. Transcription of the human sequence is under the control of the endogenous mouse promoter. The inserted human sequence segment encodes the DNA binding domain and the TRP53 polyproline domain. This latter domain contains a polymorphism at codon 72 that encodes either arginine or proline in human populations. This mutant strain expresses the proline variant at codon 72 and the related strain, 129-Trp53^tm1Holl/J (Stock No. 004301) expresses the arginine variant. Mice that are homozygous for this mutation are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. Immortalized cell lines derived from primary embryonic fibroblasts harvested from these mice frequently harbor a TRP53 (p53) mutation in the DNA binding domain typical of those found in human tumors. This mutant mouse strain may be useful in studies related to spontaneous and induced mutation of the human TRP53 gene in human cancers, and for testing pharmacological agents in vivo for their activity in altering DNA-binding activity of mutant TRP53 proteins found in tumors.

Development

A targeting vector containing sequence from exons 4-9 of the human TRP53 gene encoding proline at codon 72 (human polymorphic site) and a floxed (loxP site flanked) PGKneo cassette were utilized in the construction of this mutant. The construct was electroporated into 129P2/OlaHsd derived E14.1 embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts, and the resulting chimeric animals were crossed to C57BL/6. Offspring with germline transmission of the human TRP53 sequences were crossed with a Cre recombinase-expressing strain (on a C57BL/6J background) to remove the floxed PGKneo cassette, and then backcrossed to 129 mice for 3 generations.

Allele

Symbol: Trp53^tm2Holl
Name: targeted mutation 2, Monica Hollstein
MGI accession ID: MGI:3794646
Generation method: Targeted
Attributes: Humanized sequence
Marker symbol: Trp53
Marker name: transformation related protein 53
Chromosome: 11
Strain of origin: 129P2/OlaHsd
Expressed genes: TRP53,tumor protein p53,Human
Molecular note: Exons 4 through 9 were replaced with corresponding exons from the human gene with a sequence variant in exon 4 that results in a proline at amino acid position 72. A floxed neo cassette used for selection was removed by cre mediated recombination. This mutation corresponds to the prevalent allele among humans of non-Northern European descent.