Succinate dehydrogenase complex subunit C, also known as succinate dehydrogenase cytochrome b560 subunit, mitochondrial, is a protein

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...

 that in humans is encoded by the SDHC 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...

.

Gene

The gene that codes for the SDHC protein is nuclear, even though the protein is located in the inner membrane of the mitochondria. The location of the gene in humans is on the first chromosome

Chromosome 1 (human)

Chromosome 1 is the designation for the largest human chromosome. Humans have two copies of chromosome 1, as they do with all of the autosomes, which are the non-sex chromosomes. Chromosome 1 spans about 247 million nucleotide base pairs, which are the basic units of information for DNA...

 at q21. The 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...

 is partitioned in 6 exon

Exon

An exon is a nucleic acid sequence that is represented in the mature form of an RNA molecule either after portions of a precursor RNA have been removed by cis-splicing or when two or more precursor RNA molecules have been ligated by trans-splicing. The mature RNA molecule can be a messenger RNA...

s. The expressed protein has 170 amino acids.

Function

The SDHC protein one of four nuclear-encoded subunits that comprise succinate dehydrogenase, also known as the mitochondrial complex II, a key enzyme complex of the citric acid cycle

Citric acid cycle

The citric acid cycle — also known as the tricarboxylic acid cycle , the Krebs cycle, or the Szent-Györgyi-Krebs cycle — is a series of chemical reactions which is used by all aerobic living organisms to generate energy through the oxidization of acetate derived from carbohydrates, fats and...

 and aerobic respiratory chains of mitochondria. The encoded protein is one of two integral membrane proteins that anchor other subunits of the complex, which form the catalytic core, to the inner mitochondrial membrane.

The succinate dehydrogenase (SDH) protein complex catalyzes the oxidation of succinate (succinate + ubiquinone => fumarate + ubiquinol). The SDHA

SDHA

Succinate dehydrogenase complex, subunit A, flavoprotein variant is a protein that in humans is encoded by the SDHA gene.The succinate dehydrogenase protein complex catalyzes the oxidation of succinate . The SDHA subunit is connected to the SDHB subunit on the hydrophilic, catalytic end of the...

 subunit is connected to the SDHB

SDHB

Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial also known as iron-sulfur subunit of complex II is a protein that in humans is encoded by the SDHB gene....

 subunit on the hydrophilic, catalytic end of the complex. Electrons removed from succinate transfer SDHA to SDHB and further to the SDHC/SDHD

SDHD

Succinate dehydrogenase [ubiquinone] cytochrome b small subunit, mitochondrial , also known as succinate dehydrogenase complex subunit D , is a protein that in humans is encoded by the SDHD gene....

 subunits on the hydrophobic end of the complex anchored in the mitochondrial membrane.

The SDH complex is located on the inner membrane of the mitochondria and participates in both the Citric Acid Cycle

Citric acid cycle

The citric acid cycle — also known as the tricarboxylic acid cycle , the Krebs cycle, or the Szent-Györgyi-Krebs cycle — is a series of chemical reactions which is used by all aerobic living organisms to generate energy through the oxidization of acetate derived from carbohydrates, fats and...

 and Respiratory chain.

SDHC acts as an intermediate in the basic SDH enzyme action:

1. SDHA
   SDHA
   Succinate dehydrogenase complex, subunit A, flavoprotein variant is a protein that in humans is encoded by the SDHA gene.The succinate dehydrogenase protein complex catalyzes the oxidation of succinate . The SDHA subunit is connected to the SDHB subunit on the hydrophilic, catalytic end of the...
   
    converts succinate to fumarate as part of the Citric Acid Cycle
   Citric acid cycle
   The citric acid cycle — also known as the tricarboxylic acid cycle , the Krebs cycle, or the Szent-Györgyi-Krebs cycle — is a series of chemical reactions which is used by all aerobic living organisms to generate energy through the oxidization of acetate derived from carbohydrates, fats and...
   
   . This reaction also converts FAD
   FAD
   In biochemistry, flavin adenine dinucleotide is a redox cofactor involved in several important reactions in metabolism. FAD can exist in two different redox states, which it converts between by accepting or donating electrons. The molecule consists of a riboflavin moiety bound to the phosphate...
   
    to FADH₂.
2. Electrons from the FADH₂ are transferred to the SDHB subunit iron clusters [2Fe-2S],[4Fe-4S],[3Fe-4S]. This function is part of the Respiratory chain
3. Finally the electrons are transferred to the Ubiquinone (Q) pool via the SDHC/SDHD
   SDHD
   Succinate dehydrogenase [ubiquinone] cytochrome b small subunit, mitochondrial , also known as succinate dehydrogenase complex subunit D , is a protein that in humans is encoded by the SDHD gene....
   
   subunits.

Further reading