COX15/YER141W Summary Help

Standard Name COX15
Systematic Name YER141W
Feature Type ORF, Verified
Description Protein required for the hydroxylation of heme O to form heme A; heme A is an essential prosthetic group for cytochrome c oxidase (1 and see Summary Paragraph)
Name Description Cytochrome c OXidase
Chromosomal Location
ChrV:453459 to 454919 | ORF Map | GBrowse
Gene Ontology Annotations All COX15 GO evidence and references
  View Computational GO annotations for COX15
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 4 genes
Classical genetics
Large-scale survey
17 total interaction(s) for 15 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 7
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 1
  • Reconstituted Complex: 1
  • Two-hybrid: 1

Genetic Interactions
  • Dosage Growth Defect: 2
  • Phenotypic Enhancement: 1
  • Phenotypic Suppression: 1

Expression Summary
Length (a.a.) 486
Molecular Weight (Da) 54,658
Isoelectric Point (pI) 10.97
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrV:453459 to 454919 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1461 453459..454919 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000000943

The COX15 gene encodes a mitochondrial inner membrane protein (2) involved in the synthesis of heme A (1). In this pathway, protoheme IX is converted to heme O by the action of Cox10p (3). The methyl group at C8 of heme O is then hydroxylated in a process requiring Cox15p, Yah1p (adrenodoxin), and possibly also Arh1p (adrenodoxin reductase) (4). This produces an intermediate that is further converted to heme A in an additional step catalyzed by an unidentified enzyme (5). Two heme A molecules generated by this pathway are incorporated into the Cox1p subunit of cytochrome c oxidase, which is the terminal member of the mitochondrial electron transport chain involved in cellular respiration.

Because the heme A cofactor is essential to cytochrome c oxidase and Cox15p is required for its synthesis, cox15 mutations lead to a deficiency in respiratory growth. Cytochrome c oxidase subunits are present in the cox15 mutant but are not assembled into a functional enzyme (2). The mutant accumulates heme O but lacks heme A (1).

Cox15p is well-conserved, with similarity to bacterial, fungal, and human predicted proteins (5, 1, 6). In Schizosaccharomyces pombe, one gene contains similarity to both COX15 and YAH1; its expression complements the S. cerevisiae cox15 yah1 double mutation (1).

Last updated: 2006-07-20 Contact SGD

References cited on this page View Complete Literature Guide for COX15
1) Barros MH, et al.  (2001) Involvement of mitochondrial ferredoxin and Cox15p in hydroxylation of heme O. FEBS Lett 492(1-2):133-8
2) Glerum DM, et al.  (1997) COX15 codes for a mitochondrial protein essential for the assembly of yeast cytochrome oxidase. J Biol Chem 272(30):19088-94
3) Tzagoloff A, et al.  (1993) On the functions of the yeast COX10 and COX11 gene products. Biochem Mol Biol Int 31(3):593-8
4) Barros MH, et al.  (2002) Mitochondrial ferredoxin is required for heme A synthesis in Saccharomyces cerevisiae. J Biol Chem 277(12):9997-10002
5) Barrientos A, et al.  (2002) Cytochrome oxidase in health and disease. Gene 286(1):53-63
6) Petruzzella V, et al.  (1998) Identification and characterization of human cDNAs specific to BCS1, PET112, SCO1, COX15, and COX11, five genes involved in the formation and function of the mitochondrial respiratory chain. Genomics 54(3):494-504