Potassium voltage-gated channel subfamily C member 2 is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...
that in humans is encoded by the ''KCNC2''
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
.
The
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...
encoded by this gene is a
voltage-gated potassium channel subunit (Kv3.2).
Expression pattern
K
v3.1 and K
v3.2 channels are prominently expressed in
neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. ...
s that fire at high frequency. K
v3.2 channels are prominently expressed in brain (fast-spiking GABAergic interneurons of the
neocortex,
hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, ...
, and
caudate nucleus
The caudate nucleus is one of the structures that make up the corpus striatum, which is a component of the basal ganglia in the human brain. While the caudate nucleus has long been associated with motor processes due to its role in Parkinson's d ...
; terminal fields of thalamocortical projections), and in
retinal ganglion cells
A retinal ganglion cell (RGC) is a type of neuron located near the inner surface (the ganglion cell layer) of the retina of the eye. It receives visual information from photoreceptors via two intermediate neuron types: bipolar cells and retina ...
.
Physiological role
K
v3.1/K
v3.2 conductance is necessary and kinetically optimized for high-frequency action potential generation.
Sometimes in heteromeric complexes with K
v3.1; important for the high-frequency firing of fast spiking GABAergic interneurons and retinal ganglion cells; and GABA release via regulation of action potential duration in presynaptic terminals.
Pharmacological properties
K
v3.2 currents in heterologous systems are highly sensitive to external
tetraethylammonium
Tetraethylammonium (TEA), () or (Et4N+) is a quaternary ammonium cation consisting of four ethyl groups attached to a central nitrogen atom, and is positively charged. It is a counterion used in the research laboratory to prepare lipophilic salts ...
(TEA) or
4-aminopyridine (4-AP) (IC
50 values are 0.1 mM for both of the drugs).
This can be useful in identifying native channels.
Transcript variants
There are four
transcript variants
Alternative splicing, or alternative RNA splicing, or differential splicing, is an alternative splicing process during gene expression that allows a single gene to code for multiple proteins. In this process, particular exons of a gene may be ...
of K
v3.2 gene: K
v3.2a, K
v3.2b, K
v3.2c, K
v3.2d. K
v3.2 isoforms differ only in their
C-terminal
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...
sequence.
References
External links
*
*
Ion channels
{{membrane-protein-stub