B6.129S1-Car4^tm1Sly/J

Stock number: 008217
Research areas: Neurobiology Research

Description

Mice that are homozygous for this targeted mutation exhibit decreased sensitivity to an inhibitor, benzolamide, of pH regulation in the extracellular space in the hippocampus when compared to wildtype controls. This mutant mouse strain may be useful in studies of pH shifts that accompany neuronal activity and neuronal physiology.

Detailed description

Mice that are homozygous for this targeted mutation exhibit decreased sensitivity to an inhibitor of pH regulation (benzolamide) in the extracellular space in the hippocampus when compared to wildtype controls. No gene product (mRNA or protein) is detected by RT-PCR or Western blot analysis of brain, heart, kidney, liver, and muscle tissue. Exons 1b, 2, and 3, a portion of exon 4, which encode three active-site His residues, are disrupted and results in early termination in exon 4. Fewer than expected homozygotes are produced from heterozygote crosses (with even fewer female homozygotes produced). Surviving homozygotes from heterozygote crosses are fertile when crossed to wildtype mice, normal in size and do not display any gross physical or behavioral abnormalities. Homozygous crosses produce small litters and pups do not survive. This mutant mouse strain may be useful in neuronal physiology related studies, especially those involving pH shifts that accompany neuronal activity.

Development

A tACE-CRE-neo^r targeting vector containing neomycin resistance, cre recombinase and the mouse Ace (angiotensin I converting enzyme (peptidyl-dipeptidase A) 1) genes was used to disrupt exons 1b, 2, 3, and a portion of exon 4. The disruption of these exons, which encode three active-site His residues, results in an early termination in exon 4. The construct was electroporated into 129S1/Sv-Oca2⁺ Tyr⁺ Kitl^Sl-J/J derived W9.5s embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6J blastocysts. The self-excising targeting vector is removed during spermatogenesis in the male chimeric animals, leaving one loxP site. The mice were then backcrossed to C57BL/6 for 20 generations before arriving at The Jackson Laboratory.

Allele

Symbol: Car4^tm1Sly
Name: targeted mutation 1, William S Sly
MGI accession ID: MGI:3611770
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Car4
Marker name: carbonic anhydrase 4
Chromosome: 11
Strain of origin: 129S1/Sv-Oca2⁺ Tyr⁺ Kitl^Sl-J/J
Molecular note: The self-excising tACE-CRE-neo cassette replaced exons 1b, 2, 3, and 9 amino acids of exon 4. This sequence encodes all three active site His residues in the 146 amino acids of the protein that immediately follow the signal sequence. The resulting frameshift produced an early termination in exon 4. Absence of transcript was confirmed by RT-PCR of mutant brain, heart, kidney and muscle. Western blot analyses of the same tissues did not detect protein.
General note: ES cell line = W9.5s