P20788 · UCRI_RAT

  • Protein
    Cytochrome b-c1 complex subunit Rieske, mitochondrial
  • Gene
    Uqcrfs1
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

function

Cytochrome b-c1 complex subunit Rieske, mitochondrial

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. The Rieske protein is a catalytic core subunit containing a [2Fe-2S] iron-sulfur cluster. It cycles between 2 conformational states during catalysis to transfer electrons from the quinol bound in the Q0 site in cytochrome b to cytochrome c1 (By similarity).
Incorporation of UQCRFS1 is the penultimate step in complex III assembly (By similarity).

Cytochrome b-c1 complex subunit 9

Component of the ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII). UQCRFS1 undergoes proteolytic processing once it is incorporated in the complex III dimer. One of the fragments, called subunit 9, corresponds to its mitochondrial targeting sequence (MTS) (By similarity).
The proteolytic processing is necessary for the correct insertion of UQCRFS1 in the complex III dimer, but the persistence of UQCRFS1-derived fragments may prevent newly imported UQCRFS1 to be processed and assembled into complex III and is detrimental for the complex III structure and function (By similarity).

Miscellaneous

The Rieske protein is a high potential 2Fe-2S protein.

Caution

Several peptides are generated during UQCRFS1 insertion. According to some authors, the identification of the transit peptide as the subunit 9, does not necessary imply that it must be considered as a structural subunit of the complex III dimer as additional fragments from UQCRFS1 are also present.

Catalytic activity

Cofactor

[2Fe-2S] cluster (UniProtKB | Rhea| CHEBI:190135 )

Note: Binds 1 [2Fe-2S] cluster per subunit. Fe-S cluster delivery to the Rieske protein is mediated by components of the iron sulfur (Fe-S) cluster assembly machinery that reside in the mitochondrial matrix (including HSC20 and LYRM7) (By similarity).

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site217[2Fe-2S] cluster (UniProtKB | ChEBI)
Binding site219[2Fe-2S] cluster (UniProtKB | ChEBI)
Binding site236[2Fe-2S] cluster (UniProtKB | ChEBI)
Binding site239[2Fe-2S] cluster (UniProtKB | ChEBI)
Binding site241[2Fe-2S] cluster (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentmitochondrial membrane
Cellular Componentmitochondrial respiratory chain complex III
Cellular Componentmitochondrial respiratory chain complex IV
Cellular Componentmitochondrion
Cellular Componentrespiratory chain complex III
Molecular Function2 iron, 2 sulfur cluster binding
Molecular Functionmetal ion binding
Molecular Functionoxidoreductase activity
Molecular Functionprotein-containing complex binding
Molecular Functionubiquinol-cytochrome-c reductase activity
Biological Processmitochondrial electron transport, ubiquinol to cytochrome c
Biological Processmitochondrial respiratory chain complex III assembly
Biological Processrespiratory electron transport chain
Biological Processresponse to hormone
Biological Processresponse to xenobiotic stimulus

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Cytochrome b-c1 complex subunit Rieske, mitochondrial
  • EC number
  • Alternative names
    • Complex III subunit 5
    • Cytochrome b-c1 complex subunit 5
    • Liver regeneration-related protein LRRGT00195
    • Rieske iron-sulfur protein (RISP)
    • Rieske protein UQCRFS1
    • Ubiquinol-cytochrome c reductase iron-sulfur subunit
  • Cleaved into 1 chains
    • Cytochrome b-c1 complex subunit 9
      (Su9
      ; Subunit 9
      ) Alternative names: 8 kDa subunit 9
      , Complex III subunit IX, Cytochrome b-c1 complex subunit 11, UQCRFS1 mitochondrial targeting sequence (UQCRFS1 MTS) , Ubiquinol-cytochrome c reductase 8 kDa protein

Gene names

    • Name
      Uqcrfs1

Organism names

  • Taxonomic identifier
  • Strain
    • Sprague-Dawley
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Glires > Rodentia > Myomorpha > Muroidea > Muridae > Murinae > Rattus

Accessions

  • Primary accession
    P20788
  • Secondary accessions
    • Q6QI13

Proteomes

Organism-specific databases

Subcellular Location

Features

Showing features for topological domain, transmembrane.

TypeIDPosition(s)Description
Topological domain79-103Mitochondrial matrix
Transmembrane104-140Helical
Topological domain141-274Mitochondrial intermembrane

Keywords

PTM/Processing

Features

Showing features for chain, disulfide bond.

TypeIDPosition(s)Description
ChainPRO_00003072481-78Cytochrome b-c1 complex subunit 9
ChainPRO_000003067179-274Cytochrome b-c1 complex subunit Rieske, mitochondrial
Disulfide bond222↔238

Post-translational modification

Proteolytic processing is necessary for the correct insertion of UQCRFS1 in the complex III dimer. Several fragments are generated during UQCRFS1 insertion, most probably due to the endogenous matrix-processing peptidase (MPP) activity of the 2 core protein subunits UQCRC1/QCR1 and UQCRC2/QCR2, which are homologous to the 2 mitochondrial-processing peptidase (MPP) subunits beta-MPP and alpha-MPP respectively. The action of the protease is also necessary for the clearance of the UQCRFS1 fragments.

Keywords

Proteomic databases

PTM databases

Expression

Gene expression databases

Interaction

Subunit

Cytochrome b-c1 complex subunit Rieske, mitochondrial

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. 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) (By similarity).
Incorporation of the Rieske protein UQCRFS1 is the penultimate step in complex III assembly. Interacts with TTC19, which is involved in the clearance of UQCRFS1 fragments (By similarity).

Cytochrome b-c1 complex subunit 9

Component of the ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII). Subunit 9 corresponds to the mitochondrial targeting sequence (MTS) of Rieske protein UQCRFS1. It is retained after processing and incorporated inside complex III, where it remains bound to the complex and localizes between the 2 core subunits UQCRC1/QCR1 and UQCRC2/QCR2.

Protein-protein interaction databases

Structure

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain187-272Rieske

Sequence similarities

Belongs to the Rieske iron-sulfur protein family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Sequence processing
    The displayed sequence is further processed into a mature form.
  • Length
    274
  • Mass (Da)
    29,446
  • Last updated
    2004-09-13 v2
  • Checksum
    6A0E0A07E956340B
MLSVAARSGPFAPVLSATSRGVAGALRPLLQSAVPATSEPPVLDVKRPFLCRESLSGQAATRPLVATVGLNVPASVRYSHTDIKVPDFSDYRRAEVLDSTKSSKESSEARKGFSYLVTATTTVGVAYAAKNAVSQFVSSMSASADVLAMSKIEIKLSDIPEGKNMAFKWRGKPLFVRHRTKKEIDQEAAVEVSQLRDPQHDLERVKKPEWVILIGVCTHLGCVPIANAGDFGGYYCPCHGSHYDASGRIRKGPAPLNLEVPTYEFTSGDVVVVG

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AY539946
EMBL· GenBank· DDBJ
AAS66286.1
EMBL· GenBank· DDBJ
mRNA
BC085339
EMBL· GenBank· DDBJ
AAH85339.1
EMBL· GenBank· DDBJ
mRNA
M24542
EMBL· GenBank· DDBJ
AAA42051.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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