In Vivo Effects of Methionine Sulfoxide Reductase Deficiency in .

The deleterious alteration of protein structure and function due to the oxidation of methionine residues has been studied extensively in age-associated neurodegenerative disorders such as Alzheimer's and Parkinson's Disease. Methionine sulfoxide reductases (MSR) have three well-characterized biological functions. The most commonly studied function is the reduction of oxidized methionine residues back into functional methionine thus, often restoring biological function to proteins. Previous studies have successfully overexpressed and silenced MSR activity in numerous model organisms correlating its activity to longevity and oxidative stress. In the present study, we have characterized in vivo effects of MSR deficiency in . Interestingly, we found no significant phenotype in animals lacking either methionine sulfoxide reductase A (MSRA) or methionine sulfoxide reductase B (MSRB). However, lacking any known MSR activity exhibited a prolonged larval third instar development and a shortened lifespan. These data suggest an essential role of MSR in key biological processes.