COX5A
COX5A (Cytochrome C Oxidase Subunit 5A) is a Protein Coding gene. Diseases associated with COX5A include Mitochondrial Complex Iv Deficiency and Chronic Progressive External Ophthalmoplegia. Among its related pathways are Respiratory electron transport, ATP synthesis by chemiosmotic coupling, and heat production by uncoupling proteins. and Gene Expression. Gene Ontology (GO) annotations related to this gene include electron transfer activity and cytochrome-c oxidase activity.
Full Name
Cytochrome C Oxidase Subunit 5A
Function
Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Electrons originating from reduced cytochrome c in the intermembrane space (IMS) are transferred via the dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1 to the active site in subunit 1, a binuclear center (BNC) formed by heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2 water molecules using 4 electrons from cytochrome c in the IMS and 4 protons from the mitochondrial matrix.
Biological Process
Mitochondrial electron transport, cytochrome c to oxygen Source: GO_Central
Cellular Location
Mitochondrion inner membrane
Involvement in disease
Mitochondrial complex IV deficiency, nuclear type 20 (MC4DN20):
An autosomal recessive mitochondrial disorder with onset in early infancy. MC4DN20 is characterized by pulmonary arterial hypertension, poor feeding, failure to thrive, hypotonia, delayed development, increased serum lactate and metabolic acidosis. Death in infancy occurs due to cardiorespiratory failure. Patient tissues show variably decreased levels and activity of mitochondrial respiratory complex IV.