COX4I1
COX4I1 (cytochrome c oxidase subunit 4I1, also known as COX4-1, COXIV, COXIV-1 and COX4) is a nuclear-encoded subunit of cytochrome c oxidase, the terminal enzyme of the mitochondrial respiratory chain. It sits in the inner mitochondrial membrane and supports oxidative phosphorylation. Browse Assay Genie's current range of COX4I1 research reagents below, or read on for the biology behind the target.
COX4I1 is a component of cytochrome c oxidase (complex IV), the last enzyme in the mitochondrial electron transport chain that drives oxidative phosphorylation. The respiratory chain contains three multisubunit complexes: succinate dehydrogenase (complex II), ubiquinol-cytochrome c oxidoreductase (complex III) and cytochrome c oxidase (complex IV). Together they transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient across the inner membrane that drives transmembrane transport and the ATP synthase.
Cytochrome c oxidase catalyses the reduction of oxygen to water. Electrons from reduced cytochrome c in the intermembrane space pass through the dinuclear copper A centre of subunit 2 and heme A of subunit 1 to a binuclear centre formed by heme A3 and copper B. This centre reduces molecular oxygen to two water molecules using four electrons from cytochrome c and four protons from the mitochondrial matrix. The complex consists of 13 mitochondrial- and nuclear-encoded subunits. The mitochondrially encoded subunits perform electron transfer and proton pumping, while the nuclear-encoded subunits, including COX4I1, are of unknown function but may play a role in regulation and assembly of the complex.
The COX4I1 gene encodes subunit IV isoform 1 and belongs to the cytochrome c oxidase IV family. HGNC places it in the group of mitochondrial complex IV cytochrome c oxidase subunits. It lies head-to-head with the NOC4 (neighbor of COX4) gene, 3' of it, and shares a promoter with it. Related pseudogenes are found on chromosomes 13 and 14, and alternative splicing produces multiple transcript variants encoding different isoforms. Earlier names include cytochrome c oxidase subunit IV and subunit IV isoform 1. Mouse and rat both carry a Cox4i1 ortholog.
COX4I1 is a subunit of the terminal respiratory enzyme, making it a relevant marker in studies of the electron transport chain and oxidative phosphorylation.
Nuclear-encoded subunits such as COX4I1 may contribute to regulation and assembly of cytochrome c oxidase, a question studied across its 13-subunit structure.
Cytochrome c oxidase helps build the inner-membrane electrochemical gradient that drives the ATP synthase, linking COX4I1 to cellular energy metabolism.
COX4I1 shares a promoter with NOC4 in a head-to-head arrangement, offering a model for studying coordinated expression of neighbouring genes.
COX4I1 is a subunit of cytochrome c oxidase, complex IV of the mitochondrial respiratory chain, which reduces oxygen to water and contributes to the proton gradient across the inner membrane. The function of the nuclear-encoded subunits is unknown, but they may help regulate and assemble the complex.
COX4I1 is also called COX4-1, COXIV, COXIV-1 and COX4, and formerly cytochrome c oxidase subunit IV isoform 1. Alternative splicing gives multiple transcript variants that encode different isoforms, and pseudogenes exist on chromosomes 13 and 14.
Mouse and rat each have an ortholog named Cox4i1. The protein belongs to the cytochrome c oxidase IV family. Check the datasheet of any product for its validated reactivity before choosing a reagent for work in a given species.
Other cytochrome c oxidase subunits and assembly-related proteins that act alongside COX4I1 in mitochondrial complex IV.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P13073; product specifications from Assay Genie datasheets.