Association of mitochondrial antioxidant enzymes with mitochondrial DNA as integral nucleoid constituents.

ABSTRACT: Mitochondrial DNA (mtDNA) is organized in protein-DNA macrocomplexes called nucleoids. Average nucleoids contain 2-8 mtDNA molecules, which are organized by the histone-like mitochondrial transcription factor A. Besides well-characterized constituents, such as single-stranded binding protein or polymerase gamma (Pol gamma), various other proteins with ill-defined functions have been identified. We report for the first time that mammalian nucleoids contain essential enzymes of an integral antioxidant system. Intact nucleoids were isolated with sucrose density gradients from rat and bovine heart as well as human Jurkat cells. Manganese superoxide dismutase (SOD2) was detected by Western blot in the nucleoid fractions. DNA, mitochondrial glutathione peroxidase (GPx1), and Pol gamma were coimm

SUBMITTER: Kienhofer J 

PROVIDER: S-EPMC2704585 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature