B6;129P2-Polk^tm1.1Rsky/J

Stock number: 009661
Research areas: Cancer Research, Cell Biology Research, Research Tools

Description

MEFs from mice that are homozygous for this targeted mutation of Polk (polymerase (DNA directed), kappa) are more sensitive to UV radiation. Homozygous males have a higher spontaneous expanded simple tandem repeat (ESTR) mutation rate in the germline when compared to wildtype controls. This mutant mouse strain may be useful in studies of DNA repair.

Detailed description

Mice that are homozygous for the targeted mutation are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. A truncated gene product (mRNA) is detected by Northern blot and RT-PCR analysis. Immunohistochemical analysis of testis did not detect the protein. MEFs from homozygous mice are more sensitive to UV radiation. Homozygous males have a higher spontaneous expanded simple tandem repeat (ESTR) mutation rate in the germline when compared to wildtype controls. This mutant mouse strain may be useful in studies of DNA repair.

Development

A loxP site flanked targeting vector containing neomycin resistance and thymidine kinase genes was utilized in the construction of this mutant. This selection cassette was inserted downstream of exon 6 of the targeted gene, and another loxP site was inserted upstream of exon 6. The construct was electroporated into 129P2/OlaHsd derived IB10 embryonic stem (ES) cells. Correctly targeted ES cells were injected into CB.20 blastocysts. The resulting chimeric animals were crossed to Cre-deleter mice (transgenic mice expressing Cre recombinase under the control of the CMV promoter) to remove the floxed neo selection cassette and exon 6. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J to establish the colony.

Allele

Symbol: Polk^tm1.1Rsky
Name: targeted mutation 1.1, Klaus Rajewsky
MGI accession ID: MGI:2445458
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Polk
Marker name: polymerase (DNA directed), kappa
Chromosome: 13
Strain of origin: 129P2/OlaHsd
Molecular note: A loxP-flanked exon 6 and downstream floxed neo cassette were removed by crossing chimeric animals to a cre deleter strain resulting in the deletion of essential catalytic residues apartate 197 and glutamate 198, as well as a frameshift mutation via splicing from exon 5 to exon 7. RT-PCR analysis of testis RNA confirmed the presence of a shorter transcript in mutant animals. Northern blot analysis showed that the mutant transcript is expressed at 5 times less than the wild-type allele.