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Extracellular superoxide dismutase polymorphism in mice: Allele-specific effects on phenotype
Sujung Jun1, Anson Pierce, Ladislav Dory
1Department of Molecular Biology & Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
Free Radical Biology & Medicine
|December 17, 2009
Summary
Extracellular superoxide dismutase (ecSOD) variants influence enzyme activity and levels. Congenic mice show the 129 allele drives ecSOD phenotype, aiding oxidative stress research.
Area of Science:
- Biochemistry
- Genetics
- Physiology
Background:
- Extracellular superoxide dismutase (ecSOD) protects against oxidative stress.
- A novel ecSOD allele in 129P3/J mice exhibits distinct biochemical properties compared to wild-type.
- This allele is linked to elevated circulating and heparin-releasable ecSOD activity.
Purpose of the Study:
- To generate and characterize congenic mice with the 129 ecSOD allele in a C57BL/6J background.
- To investigate the allele-driven versus genome-driven contributions to ecSOD phenotype.
- To establish a model for studying ecSOD regulation and its role in oxidative stress-related diseases.
Main Methods:
- Extensive backcrossing to create congenic C57BL/6J mice (>99.8% genetic identity).
- SNP analysis using the Affymetrix Parallele Mouse 5K SNP panel.
- Phenotypic characterization of ecSOD activity (plasma, heparin-releasable) and mRNA levels.
Main Results:
- Congenic mice accurately recapitulated the ecSOD phenotype of the founder mice.
- The 129 ecSOD allele primarily determined enzyme expression levels and activity.
- Tissue enzyme distribution was similar, but the 129 allele showed higher expression despite lower mRNA levels.
Conclusions:
- The ecSOD phenotype is largely allele-driven, with minimal genomic influence, except for tissue mRNA levels.
- Allele-specific differences in ecSOD synthesis and secretion regulation are suggested.
- Congenic mice provide a valuable model for ecSOD research in oxidative stress conditions.
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