P80971 (COX42_THUOB) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Cytochrome c oxidase subunit 4 isoform 2, mitochondrial EC=1.9.3.1 Alternative name(s): Cytochrome c oxidase subunit IV isoform 2 Short name=COX IV-2
Organism	Thunnus obesus (Bigeye tuna)
Taxonomic identifier	8241 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Actinopterygii › Actinopteri › Neopterygii › Teleostei › Elopocephala › Clupeocephala › Euteleostei › Neognathi › Neoteleostei › Eurypterygii › Ctenosquamata › Acanthomorpha › Euacanthomorpha › Holacanthopterygii › Acanthopterygii › Euacanthopterygii › Percomorpha › Perciformes › Scombroidei › Scombridae › Scombrinae › Thunnini › Thunnus

Protein attributes

Sequence length	176 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	This protein is one of the nuclear-coded polypeptide chains of cytochrome c oxidase, the terminal oxidase in mitochondrial electron transport.
Catalytic activity	4 ferrocytochrome c + O2 + 4 H+ = 4 ferricytochrome c + 2 H2O.
Subcellular location	Mitochondrion inner membrane.
Sequence similarities	Belongs to the cytochrome c oxidase IV family.

Ontologies

Keywords
Cellular component	Membrane Mitochondrion Mitochondrion inner membrane
Domain	Transit peptide
Molecular function	Oxidoreductase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Cellular_component	mitochondrial inner membrane Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	cytochrome-c oxidase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Transit peptide	1 – 28	28	Mitochondrion Ref.2
	Chain	29 – 176	148	Cytochrome c oxidase subunit 4 isoform 2, mitochondrial		PRO_0000006093
Experimental info
	Sequence conflict	33	1	L → H AA sequence Ref.2

Sequences

	Sequence		Length	Mass (Da)
	P80971 [UniParc]. Last modified April 3, 2002. Version 2. Checksum: 4EEB4EF17BC58AD4	FASTA	176	20,470
	10 20 30 40 50 60 MLRLTAGRVR SLLAGRATAA FSTSSARMAS HDLEVAESVD MSKPLYWDRL DTPLPDRPYK 70 80 90 100 110 120 EDLTAADKSL KQKEKGPWGQ LSKEEKIALY RLMFCQTYSE MKQPSSEWKT VFGGIFIFLG 130 140 150 160 170 FTGLVVWWQA LYVYPPRPRT FDDEWKAKQL KRMLDMRVNP IEGFSAKWDY EKGQWK

References

[1]	"New isoforms of cytochrome c oxidase subunit IV in tuna fish." Huettemann M. Biochim. Biophys. Acta 1492:242-246(2000) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Heart, Liver and Muscle.
[2]	"The subunit structure of cytochrome-c oxidase from tuna heart and liver." Arnold S., Lee I., Kim M., Song E., Linder D., Lottspeich F., Kadenbach B. Eur. J. Biochem. 248:99-103(1997) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 29-38. Tissue: Heart and Liver.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF204871 mRNA. Translation: AAF79934.1.
PIR	S77980.
3D structure databases
ProteinModelPortal	P80971.
SMR	P80971. Positions 34-176.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Phylogenomic databases
HOVERGEN	HBG051087.
Family and domain databases
Gene3D	1.10.442.10. 1 hit.
InterPro	IPR013288. Cyt_c_oxidase_su4. IPR004203. Cyt_c_oxidase_su4_fam. [Graphical view]
Pfam	PF02936. COX4. 1 hit. [Graphical view]
PRINTS	PR01873. CYTCOXIDASE4.
SUPFAM	SSF81406. COX4. 1 hit.
ProtoNet	Search...

Entry information

Entry name

COX42_THUOB

Accession

Primary (citable) accession number: P80971
Secondary accession number(s): Q9I8T9

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1997
Last sequence update:	April 3, 2002
Last modified:	April 3, 2013
This is version 63 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program