CHRNA5 Membrane Protein Introduction

Introduction of CHRNA5

CHRNA5, also known as neuronal acetylcholine receptor subunit alpha-5 (NACHRA5), is a protein that in humans is encoded by the CHRNA5 gene. The neuronal acetylcholine receptors (nAChRs) are divided into several subtypes that are formed through varying combinations of homologous subunits arranged around a central channel. So far, 12 subunits have been identified in mammals and designated as either α-type (α2-α10) or β-type (β2-β4) based on their homology to the muscle α1 subunit. Each nAChR subunit has four conserved transmembrane (TM) regions and a cytoplasmic loop of variable length and sequence. α5 subunit is an accessory subunit that forms pentamers with either α4β2, α3β4, or α3β2 subunits, and together, these constitute 10-37% of all nAChRs. Although high levels of expression are found only in few brain areas, CHRNA5 mRNA has been found in the majority of brain regions, suggesting that α5 nAChRs could have a substantial impact on brain function.

Function of CHRNA5 Membrane Protein

The majority of functional neuronal nAChRs are composed of two α and three β subunits, with “duplex” (α/β) or “triplex” combinations (α_xα_yβ or αβ_xβ_y). The α5 subunit is involved in nAChR receptors with α_xα_yβ combinations but cannot yield functional receptors when expressed alone or in combination with β subunits only. Although the α5 subunit is not necessary for the assembly of functional receptors, they can alter the pharmacological and biophysical properties of nAChR, and these effects depend on the nature of the subunit co-expressed with α5. When co-expressed with α3 and α2, α5 increases sensitivity to ACh, but this effect is not observed when α2 is replaced by α4. In contrast, the presence of α5 increases the calcium permeability and desensitization rate in nAChRs containing α3β2 and α3β4. In the peripheral nervous system, α5 is found in the sympathetic and parasympathetic ganglia where the nAChRs containing α5 may affect the autonomic control of several organ systems. In the central nervous system, α5 is highly expressed in the CA1 area of the hippocampus, the interpeduncular nucleus, the ventral tegmental area (VTA), and the substantia nigra compacta, where nAChRs could potentially influence learning, memory, and drug-seeking behaviors.

Fig 1 (a) Schematic representation of the pentamer arrangement of the subunits in the assembled nAChR. (b) Conserved domains of the nAChR subunit, including amino (N) and carboxy (C) terminals, transmembrane domains (M1–M4) and the intracellular loop.

Application of CHRNA5 Membrane Protein Literature

1. Dawson A., et al. Knockout of alpha 5 nicotinic acetylcholine receptors subunit alters ethanol-mediated behavioral effects and reward in mice. Neuropharmacology. 2018, 138:341-348. PubMed ID:29944862
   
   

   This article finds that deletion of the alpha 5 nAChR subunit enhances ethanol-induced hypothermia, hypnosis, and anxiolytic-like response compared to wild-type controls. Alpha 5 nAChR is involved in some but not all behavioral effects of ethanol, emphasizing the importance of nAChRs as a possible target for the treatment of alcohol dependence.

2. Tomaz P.R.X., et al. Cholinergic receptor nicotinic alpha 5 subunit polymorphisms are associated with smoking cessation success in women. Bmc Medical Genetics. 2018, 19(1):55. PubMed ID:29621993
   
   

   This paper shows that CHRNA5 rs16969968 and rs2036527 polymorphisms are associated with higher success rate in the smoking cessation in women.

3. Jin X., et al. The nicotinic α5 subunit can replace either an acetylcholine-binding or nonbinding subunit in the α4β2 neuronal nicotinic receptor. Mol Pharmacol. 2014, 85(1):11-7. PubMed ID:24184962
   
   

   This article finds that the alpha 5 subunit can occupy the position of a nonbinding subunit or replace β2 subunit involved in the canonical binding site.

4. Criado M. Acetylcholine nicotinic receptor subtypes in chromaffin cells. Journal of Physiology. 2018, 470(1):13-20. PubMed ID:28791474
   
   

   This article shows that a heteromeric assembly of α3, β4 and perhaps α5 subunits is involved in the activation step of the catecholamine secretion process and is not blocked by the snake toxin α-bungarotoxin.

5. Salas, R. The nicotinic acetylcholine receptor subunit alpha 5 mediates short-term effects of nicotine in vivo. Molecular Pharmacology. 2003, 63(5):1059-1066. PubMed ID: 12695534
   
   

   This article observes that the α5 subunit is directly involved in multiple phenotypes.

CHRNA5 Preparation Options

Membrane protein research has made significant progress over the past few years. Based on our versatile Magic™ membrane protein production platform, we could offer a range of membrane protein preparation services for worldwide customers in reconstitution forms and multiple active formats. Aided by our versatile Magic™ anti-membrane protein antibody discovery platform, we also provide customized anti-CHRNA5 antibody development services.

• Magic™ Membrane Protein Production Platform
• Magic™ Anti-Membrane Protein Antibody Discovery Platform

In the past years, Creative Biolabs has successfully produced many functional membrane proteins for our global customers. We are very honored to accelerate the development of our clients’ programs through our one-stop, custom-oriented service. For more detailed information, please feel free to contact us.

All listed services and products are For Research Use Only. Do Not use in any diagnostic or therapeutic applications.