Potassium voltage-gated channel subfamily KQT member 4, also known as voltage-gated potassium channel subunit K
v7.4, 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, respo ...
that in humans is encoded by the ''KCNQ4''
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 ba ...
.
Function
The protein encoded by this gene forms a
potassium channel
Potassium channels are the most widely distributed type of ion channel found in virtually all organisms. They form potassium-selective pores that span cell membranes. Potassium channels are found in most cell types and control a wide variety of cel ...
that is thought to play a critical role in the regulation of neuronal excitability, particularly in sensory cells of the
cochlea
The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus. A core component of the cochlea is the Organ of Corti, the sensory org ...
. The encoded protein can form a homomultimeric potassium channel or possibly a heteromultimeric channel in association with the protein encoded by the
KCNQ3
Kv7.3 (KvLQT3) is a potassium channel protein coded for by the gene KCNQ3.
It is associated with benign familial neonatal epilepsy.
The M channel is a slowly activating and deactivating potassium channel that plays a critical role in the regul ...
gene.
Clinical significance
The current generated by this channel is inhibited by
muscarinic acetylcholine receptor M1
The muscarinic acetylcholine receptor M1, also known as the cholinergic receptor, muscarinic 1, is a muscarinic receptor that in humans is encoded by the ''CHRM1'' gene. It is localized to 11q13.
This receptor is found mediating slow EPSP at ...
and activated by
retigabine
Retigabine (INN) or ezogabine (USAN) is an anticonvulsant used as an adjunctive treatment for partial epilepsies in treatment-experienced adult patients. The drug was developed by Valeant Pharmaceuticals and GlaxoSmithKline. It was approved by th ...
, a novel anti-convulsant drug. Defects in this gene are a cause of
nonsyndromic sensorineural deafness type 2 (DFNA2), an autosomal dominant form of progressive hearing loss. Two transcript variants encoding different isoforms have been found for this gene.
Ligands
* ML213: KCNQ2/Q4 channel opener.
See also
*
Voltage-gated potassium channel
Voltage-gated potassium channels (VGKCs) are transmembrane channels specific for potassium and sensitive to voltage changes in the cell's membrane potential. During action potentials, they play a crucial role in returning the depolarized ce ...
References
Further reading
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External links
GeneReviews/NCBI/NIH/UW entry on Deafness and Hereditary Hearing Loss Overview*
GeneReviews/NCBI/NIH/UW entry on DFNA2 Nonsyndromic Hearing Loss
Ion channels
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