C57BL/6-Uqcrfs1^tm1.1Hek/J

Stock number: 017721
Research areas: Developmental Biology Research, Metabolism Research, Research Tools

Description

These Risp^+/P224S mutant mice exhibit mildly impaired mitochondrial function, reduced metabolic rate (heterozygous males), and may have applications in studies of longevity, aging and mitochondrial function.

Detailed description

Ubiquinol-cytochrome c reductase, Rieske iron-sulfur polypeptide 1, is a subunit of the ubiquinol-cytochrome c reductase complex (Complex III or Cytochrome bc1 complex), of the electron transport chain, which transfers electrons from ubiquinol to cytochrome c. These mice carry a targeted mutation of the Uqcrfs1 gene, consisting of a proline-to-serine point mutation(P224S) in exon 2 that corresponds to the mutation found in isp-1(qm150) mutant Caenorhabditis elegans worms. Mice that are homozygous for the targeted mutation have an embryonic lethal phenotype. Heterozygotes are viable and fertile. Heterozygous males have a lifespan that is 10% less than wildtype controls. Female heterozygotes have an unaffected median lifespan, but those that survive to mid-life exhibit a survival advantage relative to wild type controls. Male heterozygotes, 3 months of age, exhibit decreased metabolic rate, while 3 month old heterozygous females and 2 year old heterozygotes do not. Two-year old heterozygous males exhibit impaired motor learning relative to wild type controls. A lower amount of gene product (protein) is detected by Western blot analysis of mitochondria isolated from liver of heterozygotes; the protein level is estimated to be approximately 67% of the wildtype level. Complex III enzymatic activity is reduced in liver by 20% in male heterozygotes and 15% in female heterozygotes.

Development

A targeting vector containing a FRT site flanked NEO cassette was used to replace the proline 224 codon CCC with TCG in exon 2. The construct was electroporated into unspecified C57BL/6 derived embryonic stem (ES) cells (Ingenko), which were transiently transfected with a FLPe recombinase vector to remove the selection cassette. ES cells that had successfully undergone FLPe-mediated recombination and no longer retained the cassette were injected into blastocysts. The resulting mice were backcrossed to C57BL/6J for 6 generations. Sequencing revealed a 33 bp duplication adjacent to the remaining FRT site. Upon arrival at The Jackson Laboratory, the mice were crossed to C57BL/6J (Stock No. 000664) at least once to establish the colony.

Allele

Symbol: Uqcrfs1^tm1.1Hek
Name: targeted mutation 1.1, Siegfried Hekimi
MGI accession ID: MGI:5307154
Generation method: Targeted
Marker symbol: Uqcrfs1
Marker name: ubiquinol-cytochrome c reductase, Rieske iron-sulfur polypeptide 1
Chromosome: 13
Strain of origin: C57BL/6
Molecular note: Nucleotide substitutions (CCC to TCG) result in the amino acid substitution of serine for proline at position 224 (P224S). This mutation is equivalent to one found in long-lived isp-1 (qm150) worms. Flp-mediated recombination removed the neo cassette used for selection purposes.