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General Information
Name
MITOCHONDRIAL COMPLEX II SUBUNITS
Species
D. melanogaster
Symbol
MCII
FlyBase ID
FBgg0000485
Date last reviewed
2021-02-23
Number of members
7
Description
Description

The succinate dehydrogenase complex is unique in that it functions in both the tricarboxylic acid (TCA) cycle and the electron transport chain (ETC), wherein it is referred to as Complex II. It is a heterotetrameric protein complex that is anchored to the inner mitochondrial membrane by two integral membrane proteins, Sdh3 (SDHC) and Sdh4 (SDHD). This Sdh3/Sdh4 dimer binds the peripheral membrane protein Sdh2 (SDHB), which tethers the catalytic Sdh1 (SDHA) subunit to the complex. Sdh1 harbors a covalently bound FAD cofactor that is required for the oxidation of succinate to fumarate in the TCA cycle. The two electrons that result from succinate oxidation are channeled through the three iron-sulfur clusters in Sdh2 to ubiquinone, which interacts with the complex via the Sdh3/Sdh4 membrane anchor, and thereby reduce it to ubiquinol as part of the ETC. (Adapted from PMID:24954416.)

Notes on Group

Three subunits of this complex are encoded by paralogous genes in D. melanogaster: SdhA and SdhAL; SdhB and SdhBL; SdhC and SdhCL. In each case, the first gene has widespread expression, whereas the second copy (the one with 'L' in the symbol) is expressed specifically in the testis.

Source Material
The MITOCHONDRIAL COMPLEX II SUBUNITS Gene Group has been compiled by FlyBase curators using the following publication(s): Vedelek et al., 2018, Porcelli and Marygold, 2014.9.16, Porcelli et al., 2007, Caggese et al., 2006, and Tripoli et al., 2005 .
Key Gene Ontology (GO) terms
Related Gene Groups
Other related group(s)
Members (7)
For all members:
Gene Symbol
Gene Name
Also Known As
Source Material for Membership
Succinate dehydrogenase, subunit A (flavoprotein)
Scs-fp, sdh, Succinate dehydrogenase A, succinate dehydrogenase, Succinyl coenzyme A synthetase flavoprotein subunit
Succinate dehydrogenase, subunit A (flavoprotein)-like
Succinate dehydrogenase, subunit B (iron-sulfur)
Succinate dehydrogenase B, SDH, succinate dehydrogenase
Succinate dehydrogenase, subunit B (iron-sulfur)-like
Succinate dehydrogenase, subunit C
Succinate dehydrogenase C, succinate dehydrogenase
Succinate dehydrogenase, subunit C-like
External Data
Synonyms and Secondary IDs
Synonym(s)
Respiratory chain complex II
Succinate-Coenzyme Q reductase
MITOCHONDRIAL COMPLEX II - SUCCINATE DEHYDROGENASE SUBUNITS
SDH
MITOCHONDRIAL COMPLEX II SUBUNITS
MCII
Secondary FlyBase ID(s)
References (7)