UQCRB
Encyclopedia
Ubiquinol-cytochrome c reductase binding protein, also known as UQCRB, is a protein
which in humans is encoded by the UQCRB gene
.
UQCRB is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase (UQCR, Complex III or Cytochrome bc1 complex), which consists of the products of one mitochondrially encoded gene:
and ten nuclear genes:
After processing the cleaved leader sequence of the iron-sulfur protein is retained as subunit 9, giving 11 subunits from 10 genes.
The bovine gene product (subunit 6) was sequenced under the name "ubiquinone-binding protein", however there is little or no evidence for a role in ubiquinone binding. Subunit 7 was identified as a Q-binding protein by photo-labeling with a ubiquinone analog (subsequent structures show it to be exposed to the lipid phase but not involved in either Q-binding site). Subunits 6 and 7 reverse position on going from Laemli gels to Weber&Osborne gels, and one might suspect the name "Q-binding protein" arose from confusion with subunit 7. I have been told however that this is not the case, and both proteins were separately identified as Q-binding proteins. Genome anotators improved the situation by naming its gene "UQCR binding", UQCRB.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
which in humans is encoded by the UQCRB gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Function
The ubiquinone-binding protein is a nucleus-encoded component of ubiquinol-cytochrome c oxidoreductase (Complex III; EC 1.10.2.2) in the mitochondrial respiratory chain and plays an important role in electron transfer as a complex of ubiquinone and QP-C. Complex III consists of 10 nuclear-encoded subunits and 1 mitochondrial-encoded subunit.UQCRB is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase (UQCR, Complex III or Cytochrome bc1 complex), which consists of the products of one mitochondrially encoded gene:
- MTCYTB (mitochondrial cytochrome bCytochrome bCytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
)
and ten nuclear genes:
- UQCRC1UQCRC1Cytochrome b-c1 complex subunit 1, mitochondrial is a protein that in humans is encoded by the UQCRC1 gene.Its gene product is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase , which consists of the products of one mitochondrially encoded gene, MTCYTB and ten nuclear...
, UQCRC2UQCRC2Cytochrome b-c1 complex subunit 2, mitochondrial is a protein that in humans is encoded by the UQCRC2 gene.Its gene product is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase , which consists of the products of one mitochondrially encoded gene, MTCYTB and ten nuclear...
, Cytochrome C1Cytochrome C1Cytochrome C1 is formed in the cytosol and targeted to the mitochondrial intermembrane space. It is one of the constituents of complex III, which forms the third proton pump in the mitochondrial electron transport chain....
, UQCRFS1UQCRFS1Ubiquinol-cytochrome c reductase, Rieske iron-sulfur polypeptide 1, also known as UQCRFS1, is a protein which in humans is encoded by the UQCRFS1 gene....
(Rieske proteinRieske proteinRieske proteins are iron-sulfur protein components of cytochrome bc1 complexes and cytochrome b6f complexes which were first discovered and isolated by John S. Rieske and co-workers in 1964. It is a unique [2Fe-2S] cluster in that one of the two Fe atoms is coordinated by two histidine residues...
), UQCRB (this protein), ("11kDa protein"), UQCRHUQCRHCytochrome b-c1 complex subunit 6, mitochondrial is a protein that in humans is encoded by the UQCRH gene.Its gene product is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase Cytochrome b-c1 complex subunit 6, mitochondrial is a protein that in humans is encoded by the...
(cyt c1 Hinge protein), UCRCUCRCUbiquinol-cytochrome c reductase complex , also known as UCRC or UQCR10, is a human gene.Its gene product is a subunit of the respiratory chain protein Ubiquinol Cytochrome c Reductase , which consists of the products of one mitochondrially encoded gene, MTCYTB and ten nuclear genes: UQCRC1,...
("cyt. c1 associated protein"), and ("Rieske-associated protein").
After processing the cleaved leader sequence of the iron-sulfur protein is retained as subunit 9, giving 11 subunits from 10 genes.
The bovine gene product (subunit 6) was sequenced under the name "ubiquinone-binding protein", however there is little or no evidence for a role in ubiquinone binding. Subunit 7 was identified as a Q-binding protein by photo-labeling with a ubiquinone analog (subsequent structures show it to be exposed to the lipid phase but not involved in either Q-binding site). Subunits 6 and 7 reverse position on going from Laemli gels to Weber&Osborne gels, and one might suspect the name "Q-binding protein" arose from confusion with subunit 7. I have been told however that this is not the case, and both proteins were separately identified as Q-binding proteins. Genome anotators improved the situation by naming its gene "UQCR binding", UQCRB.