Nicotinic acetylcholine receptor protein

We have used the SEC/LALLS technique to determine the molecular weight of nicotinic acetylcholine receptor protein monomer, dimer and their subunits from the electric ray, Narke japonica [9, 11]. It is known that the receptor protein monomer is composed of four kinds of subunits, a, 6, Y and a. Fig. 5 A and B show, for example, elution profiles for the receptor monomer and the a-subunit, respectively. 

Mode of Motion. Nicotine, anabasine, and imidocloprid affect the ganglia of the insect central nervous system, faciUtating transsynaptic conduction at low concentrations and blocking conduction at higher levels. The extent of ionisation of the nicotinoids plays an important role in both their penetration through the ionic barrier of the nerve sheath to the site of action and in their interaction with the site of action, which is befleved to be the acetylcholine receptor protein. There is a marked similarity in dimensions between acetylcholine and the nicotinium ion. 

Changeux, JP (1990) The nicotinic acetylcholine receptor an allosteric protein protot5q)e of ligand-gated ion channels. Trends Pharmacol. Sci. 11 485M92. 

Figure 2.1 Diagram of nicotinic acetylcholine receptor (nAChR) structure. A top view of (A) an a7 nAChR and (B) a p2 nAChR shows that homomeric and heteromeric classes of nAChRs are both pentameric in structure. Each subunit is made up of four transmembrane domains with the M2 domain making up the ion pore. (C) A side view of the four transmembrane regions shows the N terminus, C terminus, and large M3-M4 intracellular loop that make up each nAChR subunit. The extracellular loops are available for binding to ligands and the intracellular loop is available for regulation of the nAChR by intracellular signaling proteins.

Dineley, K.T., Westerman, M., Bui, D., Bell, K., Ashe, K.H., Sweatt, J.D. Beta-amyloid activates the mitogen-activated protein kinase cascade via hippocampal alpha7 nicotinic acetylcholine receptors in vitro and in vivo mechanisms related to Alzheimer s disease. J. Neurosci. 21 4125, 2001. 

Combi R, Dalpra L, Tenchini ML, Ferini-Strambi L (2004) Autosomal dominant nocturnal frontal lobe epilepsy A critical overview, J Neurol 251 923-934 Connolly J, Boulter J, Heinemann SF (1992) Alpha 4-2 beta 2 and other nicotinic acetylcholine receptor subtypes as targets of psychoactive and addictive drugs, Br J Pharmacol 105 657-666 Conti-Tronconi BM, Dunn SM, Barnard EA, DoUy JO, Lai FA, Ray N, Raftery MA (1985) Brain and muscle nicotinic acetylcholine receptors are different but homologous proteins, Proc Natl Acad Sci U S A 82 5208-5212... 

Receptors and Transport Systems Affinity labeling of receptors, 46, 572 nicotinic acetylcholine receptors, 46, 582 )8-adrenergic receptors, 46, 591 opiate receptors, 46, 601 amino acid transport proteins, 46, 607 the biotin transport system, 46, 613. 

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