Neuronal acetylcholine receptor subunit alpha-5, also known as nAChRα5, 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 ''CHRNA5''
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 encoded by this gene is a subunit of certain
nicotinic acetylcholine receptor
Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral ner ...
s (nAchR).
Function
Nicotinic acetylcholine receptors (
nAChRs), such as CHRNA5, are members of a superfamily of
ligand-gated ion channel
Ligand-gated ion channels (LICs, LGIC), also commonly referred to as ionotropic receptors, are a group of transmembrane ion-channel proteins which open to allow ions such as Na+, K+, Ca2+, and/or Cl− to pass through the membrane in res ...
s that mediate fast signal transmission at
synapses. The nAChRs are thought to be (hetero)pentamers composed of homologous subunits.
CHRNA5 is a candidate gene for predisposition to nicotine dependence and to lung cancer risk. Polymorphisms in the CHRNA5 promoter are functionally associated with CHRNA5 transcript levels in lung tissue.
[Falvella et al. Promoter polymorphisms and transcript levels of nicotinic receptor CHRNA5. J Natl Cancer Inst. 2010;102(17):1366–1370.]
Interactive pathway map
See also
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Nicotinic acetylcholine receptor
Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral ner ...
References
Further reading
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External links
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Ion channels
Nicotinic acetylcholine receptors
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