O14949 · QCR8_HUMAN
- ProteinCytochrome b-c1 complex subunit 8
- GeneUQCRQ
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Component of the ubiquinol-cytochrome c oxidoreductase, a multisubunit transmembrane complex that is part of the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. The cytochrome b-c1 complex catalyzes electron transfer from ubiquinol to cytochrome c, linking this redox reaction to translocation of protons across the mitochondrial inner membrane, with protons being carried across the membrane as hydrogens on the quinol. In the process called Q cycle, 2 protons are consumed from the matrix, 4 protons are released into the intermembrane space and 2 electrons are passed to cytochrome c.
GO annotations
all annotations | all molecular function | virus receptor activity | dna binding | rna binding | cytoskeletal motor activity | catalytic activity | gtpase activity | structural molecule activity | transporter activity | cytoskeletal protein binding | lipid binding | cyclase activity | antioxidant activity | oxidoreductase activity | transferase activity | hydrolase activity | lyase activity | isomerase activity | ligase activity | protein tag activity | cargo receptor activity | histone binding | protein folding chaperone | translation regulator activity | nutrient reservoir activity | receptor ligand activity | molecular transducer activity | molecular adaptor activity | toxin activity | cell adhesion mediator activity | molecular function regulator activity | virus coreceptor activity | catalytic activity, acting on a protein | catalytic activity, acting on dna | catalytic activity, acting on rna | molecular carrier activity | transcription regulator activity | general transcription initiation factor activity | molecular sensor activity | molecular sequestering activity | atp-dependent activity | other molecular function | all biological process | mitotic cell cycle | cytokinesis | cytoplasmic translation | immune system process | muscle system process | circulatory system process | renal system process | respiratory system process | carbohydrate metabolic process | generation of precursor metabolites and energy | dna replication | dna repair | dna recombination | chromatin organization | dna-templated transcription | regulation of dna-templated transcription | trna metabolic process | protein folding | protein glycosylation | amino acid metabolic process | modified amino acid metabolic process | lipid metabolic process | vitamin metabolic process | sulfur compound metabolic process | intracellular protein transport | nucleocytoplasmic transport | autophagy | inflammatory response | mitochondrion organization | cytoskeleton organization | microtubule-based movement | peroxisome organization | lysosome organization | chromosome segregation | cell adhesion | establishment or maintenance of cell polarity | programmed cell death | photosynthesis | mrna metabolic process | snrna metabolic process | vesicle-mediated transport | reproductive process | digestive system process | signaling | cell differentiation | protein catabolic process | extracellular matrix organization | regulatory ncrna-mediated gene silencing | telomere organization | cell junction organization | wound healing | ribosome biogenesis | cilium organization | anatomical structure development | cell motility | nervous system process | endocrine process | protein maturation | transmembrane transport | nucleobase-containing small molecule metabolic process | hepaticobiliary system process | membrane organization | protein-containing complex assembly | cell wall organization or biogenesis | nitrogen cycle metabolic process | protein localization to plasma membrane | defense response to other organism | detoxification | meiotic nuclear division | mitotic nuclear division | mitochondrial gene expression | carbohydrate derivative metabolic process | other biological process | all cellular component | nuclear chromosome | extracellular region | extracellular space | cell wall | nucleus | nuclear envelope | nucleoplasm | chromosome | nucleolus | mitochondrion | lysosome | endosome | vacuole | peroxisome | endoplasmic reticulum | golgi apparatus | lipid droplet | microtubule organizing center | cytosol | ribosome | cytoskeleton | plasma membrane | cilium | plastid | thylakoid | external encapsulating structure | extracellular matrix | cytoplasmic vesicle | organelle | other cellular component | |||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Aspect | Term | |
---|---|---|
Cellular Component | mitochondrial inner membrane | |
Cellular Component | mitochondrial respiratory chain complex III | |
Cellular Component | mitochondrion | |
Biological Process | cellular respiration | |
Biological Process | cerebellar Purkinje cell layer development | |
Biological Process | hippocampus development | |
Biological Process | hypothalamus development | |
Biological Process | midbrain development | |
Biological Process | mitochondrial electron transport, ubiquinol to cytochrome c | |
Biological Process | pons development | |
Biological Process | pyramidal neuron development | |
Biological Process | subthalamus development | |
Biological Process | thalamus development |
Keywords
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameCytochrome b-c1 complex subunit 8
- Alternative names
Gene names
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo
Accessions
- Primary accessionO14949
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
UniProt Annotation
GO Annotation
Mitochondrion inner membrane ; Single-pass membrane protein
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Topological domain | 2-39 | Mitochondrial matrix | ||||
Sequence: GREFGNLTRMRHVISYSLSPFEQRAYPHVFTKGIPNVL | ||||||
Transmembrane | 40-68 | Helical | ||||
Sequence: RRIRESFFRVVPQFVVFYLIYTWGTEEFE | ||||||
Topological domain | 69-82 | Mitochondrial intermembrane | ||||
Sequence: RSKRKNPAAYENDK |
Keywords
- Cellular component
Disease & Variants
Involvement in disease
Mitochondrial complex III deficiency, nuclear type 4 (MC3DN4)
- Note
- DescriptionA disorder of the mitochondrial respiratory chain resulting in a highly variable phenotype depending on which tissues are affected. Clinical features include mitochondrial encephalopathy, psychomotor retardation, ataxia, severe failure to thrive, liver dysfunction, renal tubulopathy, muscle weakness and exercise intolerance.
- See alsoMIM:615159
Natural variants in MC3DN4
Variant ID | Position(s) | Change | Description | |
---|---|---|---|---|
VAR_045911 | 45 | S>F | in MC3DN4; dbSNP:rs11544803 |
Features
Showing features for natural variant.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Natural variant | VAR_045911 | 45 | in MC3DN4; dbSNP:rs11544803 | |||
Sequence: S → F |
Variants
We now provide the "Disease & Variants" viewer in its own tab.
The viewer provides 115 variants from UniProt as well as other sources including ClinVar and dbSNP.
Keywords
- Disease
Organism-specific databases
Miscellaneous
Chemistry
Genetic variation databases
PTM/Processing
Features
Showing features for initiator methionine, chain, modified residue, modified residue (large scale data).
Type | ID | Position(s) | Source | Description | |||
---|---|---|---|---|---|---|---|
Initiator methionine | 1 | UniProt | Removed | ||||
Sequence: M | |||||||
Chain | PRO_0000193544 | 2-82 | UniProt | Cytochrome b-c1 complex subunit 8 | |||
Sequence: GREFGNLTRMRHVISYSLSPFEQRAYPHVFTKGIPNVLRRIRESFFRVVPQFVVFYLIYTWGTEEFERSKRKNPAAYENDK | |||||||
Modified residue | 16 | UniProt | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue (large scale data) | 16 | PRIDE | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue (large scale data) | 18 | PRIDE | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue | 33 | UniProt | N6-acetyllysine; alternate | ||||
Sequence: K | |||||||
Modified residue | 33 | UniProt | N6-succinyllysine; alternate | ||||
Sequence: K |
Keywords
- PTM
Proteomic databases
PTM databases
Interaction
Subunit
Component of the ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII), a multisubunit enzyme composed of 11 subunits. The complex is composed of 3 respiratory subunits cytochrome b, cytochrome c1 and Rieske protein UQCRFS1, 2 core protein subunits UQCRC1/QCR1 and UQCRC2/QCR2, and 6 low-molecular weight protein subunits UQCRH/QCR6, UQCRB/QCR7, UQCRQ/QCR8, UQCR10/QCR9, UQCR11/QCR10 and subunit 9, the cleavage product of Rieske protein UQCRFS1 (By similarity).
The complex exists as an obligatory dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with NADH-ubiquinone oxidoreductase (complex I, CI) and cytochrome c oxidase (complex IV, CIV), resulting in different assemblies (supercomplex SCI1III2IV1 and megacomplex MCI2III2IV2) (PubMed:28844695).
Interacts with UQCC6 (By similarity).
The complex exists as an obligatory dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with NADH-ubiquinone oxidoreductase (complex I, CI) and cytochrome c oxidase (complex IV, CIV), resulting in different assemblies (supercomplex SCI1III2IV1 and megacomplex MCI2III2IV2) (PubMed:28844695).
Interacts with UQCC6 (By similarity).
Protein-protein interaction databases
Miscellaneous
Structure
Sequence
- Sequence statusComplete
- Length82
- Mass (Da)9,906
- Last updated2007-01-23 v4
- Checksum5ED13ABDD2990DD2
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 73-82 | in Ref. 1; BAA23321 | ||||
Sequence: KNPAAYENDK → RIQLPMKMTNEQRIRMTVPCL |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
D50369 EMBL· GenBank· DDBJ | BAA23321.1 EMBL· GenBank· DDBJ | mRNA | ||
BC001390 EMBL· GenBank· DDBJ | AAH01390.1 EMBL· GenBank· DDBJ | mRNA | ||
BC090048 EMBL· GenBank· DDBJ | AAH90048.1 EMBL· GenBank· DDBJ | mRNA |