ID   COX3_CHICK              Reviewed;         261 AA.
AC   P18945;
DT   01-NOV-1990, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1990, sequence version 1.
DT   24-JAN-2024, entry version 148.
DE   RecName: Full=Cytochrome c oxidase subunit 3;
DE            EC=7.1.1.9;
DE   AltName: Full=Cytochrome c oxidase polypeptide III;
GN   Name=MT-CO3; Synonyms=COIII, COXIII, MTCO3;
OS   Gallus gallus (Chicken).
OG   Mitochondrion.
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Archelosauria; Archosauria; Dinosauria; Saurischia; Theropoda;
OC   Coelurosauria; Aves; Neognathae; Galloanserae; Galliformes; Phasianidae;
OC   Phasianinae; Gallus.
OX   NCBI_TaxID=9031;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC   STRAIN=Red jungle fowl {ECO:0000312|Proteomes:UP000000539};
RX   PubMed=2329578; DOI=10.1016/0022-2836(90)90225-b;
RA   Desjardins P., Morais R.;
RT   "Sequence and gene organization of the chicken mitochondrial genome. A
RT   novel gene order in higher vertebrates.";
RL   J. Mol. Biol. 212:599-634(1990).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=1662904; DOI=10.1152/ajpcell.1991.261.6.c1091;
RA   Kennedy J.M., Lobacz S.R., Kelley S.W.;
RT   "Mitochondrial DNA replication and transcription are dissociated during
RT   embryonic cardiac hypertrophy.";
RL   Am. J. Physiol. 261:C1091-C1098(1991).
CC   -!- FUNCTION: Component of the cytochrome c oxidase, the last enzyme in the
CC       mitochondrial electron transport chain which drives oxidative
CC       phosphorylation. The respiratory chain contains 3 multisubunit
CC       complexes succinate dehydrogenase (complex II, CII), ubiquinol-
CC       cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III,
CC       CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to
CC       transfer electrons derived from NADH and succinate to molecular oxygen,
CC       creating an electrochemical gradient over the inner membrane that
CC       drives transmembrane transport and the ATP synthase. Cytochrome c
CC       oxidase is the component of the respiratory chain that catalyzes the
CC       reduction of oxygen to water. Electrons originating from reduced
CC       cytochrome c in the intermembrane space (IMS) are transferred via the
CC       dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1
CC       to the active site in subunit 1, a binuclear center (BNC) formed by
CC       heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2
CC       water molecules using 4 electrons from cytochrome c in the IMS and 4
CC       protons from the mitochondrial matrix. {ECO:0000250|UniProtKB:P00420}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=4 Fe(II)-[cytochrome c] + 8 H(+)(in) + O2 = 4 Fe(III)-
CC         [cytochrome c] + 4 H(+)(out) + 2 H2O; Xref=Rhea:RHEA:11436,
CC         Rhea:RHEA-COMP:10350, Rhea:RHEA-COMP:14399, ChEBI:CHEBI:15377,
CC         ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:29033,
CC         ChEBI:CHEBI:29034; EC=7.1.1.9;
CC         Evidence={ECO:0000250|UniProtKB:P00420};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437;
CC         Evidence={ECO:0000250|UniProtKB:P00420};
CC   -!- SUBUNIT: Component of the cytochrome c oxidase (complex IV, CIV), a
CC       multisubunit enzyme composed of 14 subunits. The complex is composed of
CC       a catalytic core of 3 subunits MT-CO1, MT-CO2 and MT-CO3, encoded in
CC       the mitochondrial DNA, and 11 supernumerary subunits COX4I, COX5A,
CC       COX5B, COX6A, COX6B, COX6C, COX7A, COX7B, COX7C, COX8 and NDUFA4, which
CC       are encoded in the nuclear genome. The complex exists as a monomer or a
CC       dimer and forms supercomplexes (SCs) in the inner mitochondrial
CC       membrane with NADH-ubiquinone oxidoreductase (complex I, CI) and
CC       ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex
CC       III, CIII), resulting in different assemblies (supercomplex
CC       SCI(1)III(2)IV(1) and megacomplex MCI(2)III(2)IV(2)).
CC       {ECO:0000250|UniProtKB:P00415}.
CC   -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC       {ECO:0000250|UniProtKB:P00415}; Multi-pass membrane protein
CC       {ECO:0000250|UniProtKB:P00415}.
CC   -!- SIMILARITY: Belongs to the cytochrome c oxidase subunit 3 family.
CC       {ECO:0000305}.
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DR   EMBL; X52392; CAA36631.1; -; Genomic_DNA.
DR   PIR; S10193; S10193.
DR   RefSeq; NP_006921.2; NC_001323.1.
DR   AlphaFoldDB; P18945; -.
DR   SMR; P18945; -.
DR   STRING; 9031.ENSGALP00000050525; -.
DR   PaxDb; 9031-ENSGALP00000034618; -.
DR   Ensembl; ENSGALT00000061564; ENSGALP00000050525; ENSGALG00000035334.
DR   Ensembl; ENSGALT00010000024.1; ENSGALP00010000008.1; ENSGALG00010000024.1.
DR   VEuPathDB; HostDB:geneid_63549467; -.
DR   eggNOG; KOG4664; Eukaryota.
DR   GeneTree; ENSGT00390000013064; -.
DR   HOGENOM; CLU_044071_0_0_1; -.
DR   InParanoid; P18945; -.
DR   OMA; SIYWWGS; -.
DR   Reactome; R-GGA-5628897; TP53 Regulates Metabolic Genes.
DR   Reactome; R-GGA-611105; Respiratory electron transport.
DR   Reactome; R-GGA-9707564; Cytoprotection by HMOX1.
DR   PRO; PR:P18945; -.
DR   Proteomes; UP000000539; Mitochondrion.
DR   Bgee; ENSGALG00000035334; Expressed in cerebellum and 13 other cell types or tissues.
DR   ExpressionAtlas; P18945; baseline and differential.
DR   GO; GO:0005751; C:mitochondrial respiratory chain complex IV; IEA:Ensembl.
DR   GO; GO:0005739; C:mitochondrion; IDA:AgBase.
DR   GO; GO:0045277; C:respiratory chain complex IV; ISS:UniProtKB.
DR   GO; GO:0004129; F:cytochrome-c oxidase activity; IEA:UniProtKB-EC.
DR   GO; GO:0006123; P:mitochondrial electron transport, cytochrome c to oxygen; IBA:GO_Central.
DR   GO; GO:0008535; P:respiratory chain complex IV assembly; IEA:Ensembl.
DR   CDD; cd01665; Cyt_c_Oxidase_III; 1.
DR   Gene3D; 1.10.287.70; -; 1.
DR   Gene3D; 1.20.120.80; Cytochrome c oxidase, subunit III, four-helix bundle; 1.
DR   InterPro; IPR024791; Cyt_c/ubiquinol_Oxase_su3.
DR   InterPro; IPR033945; Cyt_c_oxase_su3_dom.
DR   InterPro; IPR000298; Cyt_c_oxidase-like_su3.
DR   InterPro; IPR035973; Cyt_c_oxidase_su3-like_sf.
DR   InterPro; IPR013833; Cyt_c_oxidase_su3_a-hlx.
DR   PANTHER; PTHR11403:SF7; CYTOCHROME C OXIDASE SUBUNIT 3; 1.
DR   PANTHER; PTHR11403; CYTOCHROME C OXIDASE SUBUNIT III; 1.
DR   Pfam; PF00510; COX3; 1.
DR   SUPFAM; SSF81452; Cytochrome c oxidase subunit III-like; 1.
DR   PROSITE; PS50253; COX3; 1.
PE   3: Inferred from homology;
KW   Membrane; Mitochondrion; Mitochondrion inner membrane; Reference proteome;
KW   Translocase; Transmembrane; Transmembrane helix.
FT   CHAIN           1..261
FT                   /note="Cytochrome c oxidase subunit 3"
FT                   /id="PRO_0000183757"
FT   TOPO_DOM        1..15
FT                   /note="Mitochondrial matrix"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        16..34
FT                   /note="Helical; Name=I"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        35..40
FT                   /note="Mitochondrial intermembrane"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        41..66
FT                   /note="Helical; Name=II"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        67..72
FT                   /note="Mitochondrial matrix"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        73..105
FT                   /note="Helical; Name=III"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        106..128
FT                   /note="Mitochondrial intermembrane"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        129..152
FT                   /note="Helical; Name=IV"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        153..155
FT                   /note="Mitochondrial matrix"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        156..183
FT                   /note="Helical; Name=V"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        184..190
FT                   /note="Mitochondrial intermembrane"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        191..223
FT                   /note="Helical; Name=VI"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        224..232
FT                   /note="Mitochondrial matrix"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TRANSMEM        233..256
FT                   /note="Helical; Name=VII"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
FT   TOPO_DOM        257..261
FT                   /note="Mitochondrial intermembrane"
FT                   /evidence="ECO:0000250|UniProtKB:P00415"
SQ   SEQUENCE   261 AA;  29625 MW;  E326CB937B123BC8 CRC64;
     MAHQAHSYHM VDPSPWPIFG AAAALLTTSG LIMWFHYSST TLLTMGLLSM LLVMLQWWRD
     VVRESTFQGH HTPTVQKGLR YGMILFITSE AFFFLGFFWA FFHSSLAPTP ELGGQWPPTG
     VKPLNPLEVP LLNTAILLAS GVTVTWAHHS ITEGNRKQAI HALTLTILLG FYFTALQAME
     YHEASFSIAD SVYGSTFFVA TGFHGLHVII GSSFLTVCLL RLIKFHFTPN HHFGFEAAAW
     YWHFVDIIWL FLYMSMYWWG S
//