Characterization of Specialized mtDNA Glycosylases

Mitochondria are cytoplasmic organelles that generate cellular energy in the form of ATP by the process of oxidative phosphorylation. Mitochondria contain multiple copies of a 16.5-kb circular genome. Mitochondrial DNA (mtDNA) encodes a subset of 13 structural, 22 transfer (tRNA), and 2 ribosomal (rRNA) genes. These few polypeptides encoded by mtDNA are essential components of oxidative phosphorylation. The other proteins involved in the metabolism and processing of the mtDNA, including mtDNA regulatory factors, are encoded in the nuclear genome. Transcription of these genes takes place in the nucleus and translation in the cytoplasm is then followed by selective transport to the mitochondria.