CHRNA3
CHRNA3 (cholinergic receptor nicotinic alpha 3 subunit) encodes the alpha-3 subunit of neuronal nicotinic acetylcholine receptors, which are pentameric, ligand-gated cation channels. It contributes to synaptic transmission in the nervous system and is the defining alpha subunit of the ganglionic nicotinic receptor. Browse Assay Genie's current range of CHRNA3 research reagents below, or read on for the biology behind the target.
CHRNA3 is a component of neuronal acetylcholine receptors (nAChRs), excitatory neurotransmitter receptors that function as pentameric, ligand-gated cation channels with high calcium permeability. nAChRs mediate synaptic transmission in the nervous system and at the neuromuscular junction, and each subunit confers distinct channel properties, including activation, deactivation and desensitisation kinetics, pH sensitivity, cation permeability and binding to allosteric modulators.
The CHRNA3 protein forms heteropentameric receptors with CHRNB2 and CHRNB4, with CHRNA5 and CHRNB3 acting as accessory subunits. The CHRNA3:CHRNB4 combination predominates in neurons of the autonomic ganglia and is therefore known as the ganglionic nicotinic receptor. CHRNA3:CHRNB4 or CHRNA3:CHRNA5:CHRNB4 receptors also act in the habenulo-interpeduncular tract, where they modulate the mesolimbic dopamine system and affect reward circuits and addiction. In the hypothalamus, nicotine activation of CHRNA3:CHRNB4 receptors activates POMC neurons and decreases food intake. The subunit is also expressed in the urothelium, where it modulates reflex bladder activity by raising intracellular calcium through extracellular influx and basal ATP release.
The CHRNA3 gene encodes an alpha-type subunit, identified by its characteristic adjacent cysteine residues, and belongs to the ligand-gated ion channel family, acetylcholine receptor subfamily. Alternatively spliced transcript variants have been described. Polymorphisms in the gene have been associated with increased risk of smoking initiation and increased susceptibility to lung cancer. The protein is found at the synaptic cell membrane and cell membrane, as well as in the endoplasmic reticulum and Golgi apparatus. Earlier gene names include cholinergic receptor, nicotinic, alpha polypeptide 3.
CHRNA3:CHRNB4 is the predominant receptor in autonomic ganglion neurons, making the subunit central to studies of ganglionic nicotinic transmission.
CHRNA3-containing receptors in the habenulo-interpeduncular tract modulate the mesolimbic dopamine system, affecting reward circuits and addiction.
Polymorphisms in the CHRNA3 gene are associated with increased risk of smoking initiation and increased susceptibility to lung cancer.
Hypothalamic CHRNA3:CHRNB4 receptors link nicotine to POMC neuron activation and reduced food intake, and urothelial receptors modulate reflex bladder activity.
CHRNA3 is an alpha subunit of neuronal nicotinic acetylcholine receptors, which are pentameric, ligand-gated cation channels with high calcium permeability. It mediates synaptic transmission, is prominent in autonomic ganglia, and contributes to reward circuits, hypothalamic control of food intake and urothelial reflex activity.
CHRNA3 forms heteropentameric receptors with CHRNB2 and CHRNB4, while CHRNA5 and CHRNB3 serve as accessory subunits. CHRNA3:CHRNB4 is known as the ganglionic nicotinic receptor, and CHRNA3:CHRNA5:CHRNB4 receptors are also described in the habenulo-interpeduncular tract.
Mouse and rat both have a Chrna3 ortholog. In humans, polymorphisms in the CHRNA3 gene have been associated with increased risk of smoking initiation and susceptibility to lung cancer. Check the datasheet of any product for its validated reactivity.
Other nicotinic acetylcholine receptor alpha subunits and partner subunits with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P32297; product specifications from Assay Genie datasheets.