High levels of Parkin eliminate defective mtDNA

摘要

Mutations in mtDNA are known to cause a myriad of diseases, and somatic mutations in mtDNA have been linked to cancer, diabetes mellitus, and neurodegenerative diseases. Patients with Parkinson disease, for example, harbor more mitochondria with damaged DNA in their neurons compared with controls. Patients typically have cells that containrna mix of healthy and damaged mtDNA; the severity of disease depends on the ratio of healthy to damaged mtDNA. Inside the mitochondria, the mutated and the healthy DNA are separately packaged and rarely mix. Der-Fen Suen et al. (pp. 11835-11840) suggest that selectively eliminating the mutated mtDNA would restore the health of the cell and might be a promising strategy for treating mitochondrial diseases. The researchers report that the enzyme Parkin, which is mutated in an early onset form of Parkinson disease, controls the quality of mitochondria in flies and mice, and can essentially trigger the elimination of damaged mtDNA.