COX4 — Neurospora crassa

Summary

NCU05689, designated COX4 (cox-4) in Neurospora crassa on chromosome 3, encodes a cytochrome c oxidase subunit 5b family protein with cytochrome-c oxidase activity and zinc/metal binding. The gene product is localised to the mitochondrial inner membrane as part of respiratory chain complex IV and is associated with mitochondrial electron transport, cytochrome c to oxygen, cellular respiration, oxidative phosphorylation, proton transmembrane transport, and mitochondrial cytochrome c oxidase assembly. COX4 is also linked to maintenance of translational fidelity. Phenotypic associations include altered respiratory metabolism (both increased and decreased rates, as well as absent), increased nitrogen source utilisation, decreased mitochondrial transport, absent desiccation resistance, decreased necrotic cell death, increased mutation frequency, increased lifespan, abnormal cell cycle progression, abnormal budding patterns, and petite-negative growth. Studies of related genes in other species connect the family to additional mitochondrial functions.