Genes necessary for mitochondrial function are located in both the cell nucleus and within the mitochondria itself
. Most of the genes that contribute to mitochondrial function are in the nucleus
. However, the mitochondrial genome encodes 37 genes
- Mitochondrial DNA (mtDNA) MtDNA is in the mitochondria, within the cytoplasm of eukaryotic cells
. It encodes 13 essential subunits of the oxidative phosphorylation system, which is involved in cellular energy conversion
- Nuclear DNA (nDNA) The vast majority of proteins within the mitochondria (more than 90%) are encoded by nuclear genes
. These genes are transcribed into mRNA in the nucleus, then translated into proteins on cytoplasmic ribosomes, before being transported into the mitochondria
Mitochondria contain their own circular DNA, distinct from nuclear DNA, including genes for ribosomal RNA and transfer RNA that are necessary for synthesizing mitochondrial proteins
