Mitochondrial respiratory chain complex gene family

Genes in the mitochondrial respiratory chain complex gene family provide instructions for proteins involved in oxidative phosphorylation, also called the respiratory chain. Oxidative phosphorylation is an important cellular process that uses oxygen and simple sugars to create adenosine triphosphate (ATP), the cell's main energy source. Five protein complexes, made up of several proteins each, are involved in this process. The complexes are named complex I, complex II, complex III, complex IV, and complex V.

Oxidative phosphorylation occurs in mitochondria, which are specialized, energy-producing structures inside cells. Within mitochondria, the five protein complexes are embedded in a tightly folded membrane called the inner mitochondrial membrane. During oxidative phosphorylation, the protein complexes carry out chemical reactions that drive the production of ATP. Specifically, they create an unequal electrical charge on either side of the inner mitochondrial membrane through a step-by-step transfer of negatively charged particles called electrons. This difference in electrical charge provides the energy for ATP production.

Most DNA is contained in a cell's nucleus and is called nuclear DNA. Mitochondria also contain a small amount of DNA, known as mitochondrial DNA. The mitochondrial respiratory chain complex gene family includes genes found in nuclear DNA as well as genes found in mitochondrial DNA. Mutations in either nuclear or mitochondrial genes in the mitochondrial respiratory chain complex gene family can cause disease.