129X1/SvJ-Gzma^tm1Ley Gzmb^tm2.1Ley/J

Stock number: 010608
Product name: Gzma^-; GzmB^-
Research areas: Immunology, Inflammation and Autoimmunity Research

Description

The knock-out mutations of granzyme B (Gzmb) and granzyme A (Gzma) genes in this double mutant mouse strain display reduced CTL lytic activity and the mice may be useful in the study of cell-mediated cytotoxicity.

Detailed description

Mice that are homozygous for the targeted mutations are viable, fertile, normal in size and do not display any gross physical or behavioral abnormalities. Cytotoxic T lymphocytes (CTL) and natural killer (NK cells) derived from mutant mice exhibit a decrease in cytotoxic activity against allogenic and NK-sensitive targets. This mutant mouse strain may be useful in studies of cell-mediated cytotoxicity.

Development

The Gzmb targeting vector contains a loxP-flanked phosphotransferase cassette driven by the phosphoglycerate kinase promoter (PGK-neo). This cassette replaced the 5' untranslated region and coding sequences of exon 1 and part of intron 1. The construct was electroporated into 129X1/Sv derived RW-4 embryonic stem cells, correctly targeted ES clones were injected into C57BL/6 blastocysts and chimeras mated to 129X1/SvJ mice. The neomycin cassette was removed by transient transfection with a Cre recombinase expressing plasmid. The Gzma targeting vector was engineered to contain a PGK-hygromycin resistance cassette that was used to disrupt exon 2, which contains the histidine residue of the catalytic triad. The construct was electroporated into 129X1/Sv derived RW-4 embryonic stem cells, and the targeted ES clones injected into C57BL/6 blastocysts and chimeras mated to 129X1/SvJ mice. Double mutant mice were generated by intercrossing mice carrying each allele. Prior to arrival at The Jackson Laboratory, the strain was made homozygous for each allele.

Allele

Symbol: Gzmb^tm2.1Ley
Name: targeted mutation 2.1, Timothy J Ley
MGI accession ID: MGI:3574017
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Gzmb
Marker name: granzyme B
Chromosome: 14
Strain of origin: 129X1/SvJ
Molecular note: The PGK-neo was removed from Gzmb^tm1Ley via transient expression of cre recombinase. This allele is missing a 350bp AvrII fragment starting within the 5' untranslated region (22 bp upstream from the initiation codon), extending through exon 1 and part of intron 1.

Allele

Symbol: Gzma^tm1Ley
Name: targeted mutation 1, Timothy J Ley
MGI accession ID: MGI:3526655
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Gzma
Marker name: granzyme A
Chromosome: 13
Strain of origin: 129X1/SvJ
Molecular note: Exon 2 was replaced with a PGK-hygro resistance cassette. Absence of mRNA was demonstrated by S1 protection assay.