+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Alpha-Conotoxin ImI exhibits subtype-specific nicotinic acetylcholine receptor blockade: preferential inhibition of homomeric alpha 7 and alpha 9 receptors



Alpha-Conotoxin ImI exhibits subtype-specific nicotinic acetylcholine receptor blockade: preferential inhibition of homomeric alpha 7 and alpha 9 receptors



Molecular Pharmacology 48(2): 194-199



Through a study of cloned nicotinic receptors expressed in Xenopus oocytes, we provide evidence that alpha-conotoxin ImI, a peptide marine snail toxin that induces seizures in rodents, selectively blocks subtypes of nicotinic acetylcholine receptors. alpha-Conotoxin ImI blocks homomeric alpha 7 nicotinic receptors with the highest apparent affinity and homomeric alpha 9 receptors with 8-fold lower affinity. This toxin has no effect on receptors composed of alpha 2 beta 2, alpha 3 beta 2, alpha 4 beta 2, alpha 2 beta 4, alpha 3 beta 4, or alpha 4 beta 4 subunit combinations. In contrast to alpha-bungarotoxin, which has high affinity for alpha 7, alpha 9, and alpha 1 beta 1 gamma delta receptors, alpha-conotoxin ImI has low affinity for the muscle nAChR. Related Conus peptides, alpha-conotoxins MI and GI, exhibit a distinct specificity, strictly targeting the muscle subtype receptor but not alpha 7 or alpha 9 receptors. alpha-Conotoxins thus represent selective tools for the study of neuronal nicotinic acetylcholine receptors.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 044997146

Download citation: RISBibTeXText

PMID: 7651351


Related references

Alpha-Conotoxin MII Structure/activity studies of a potent and selective peptide antagonist of the alpha-3-beta-2 subtype of neuronal nicotinic acetylcholine receptor. Society for Neuroscience Abstracts 23(1-2): 384, 1997

Nuclear magnetic resonance solution conformation of alpha-conotoxin AuIB, an alpha(3)beta(4) subtype-selective neuronal nicotinic acetylcholine receptor antagonist. Journal of Biological Chemistry 275(12): 8680-8685, 2000

Alpha-Homomeric subtype and the functional inactivation of neuronal nicotinic acetylcholine receptors. Society for Neuroscience Abstracts 24(1-2): 1341, 1998

Solution conformation of alpha-conotoxin EI, a neuromuscular toxin specific for the alpha 1/delta subunit interface of torpedo nicotinic acetylcholine receptor. Journal of Biological Chemistry 276(52): 49028-49033, 2001

3- anabaseine a specific agonist of alpha-7 homomeric nicotinic acetylcholine receptors , releases striatal dopamine without causing a long term inhibition of DA release. Society for Neuroscience Abstracts 27(1): 621, 2001

Novel alpha-conotoxins from Conus spurius and the alpha-conotoxin EI share high-affinity potentiation and low-affinity inhibition of nicotinic acetylcholine receptors. Febs Journal 274(15): 3972-3985, 2007

Subtype-specific actions of beta-amyloid peptides on recombinant human neuronal nicotinic acetylcholine receptors (alpha 7, alpha 4 beta 2, alpha 3 beta 4) expressed in Xenopus laevis oocytes. British Journal of Pharmacology 146(7): 964-971, 2005

A new alpha-conotoxin which targets alpha-3-beta-2 nicotinic acetylcholine receptors. Journal Of Biological Chemistry. 271(13): 7522-7528, 1996

A new alpha-conotoxin which targets alpha-3-beta-2 nicotinic acetylcholine receptors. Society for Neuroscience Abstracts 21(1-3): 1334, 1995

A novel alpha conotoxin (alpha-PIB) isolated from C. purpurascens is selective for skeletal muscle nicotinic acetylcholine receptors. Toxicon 49(8): 1193-1199, 2007

Species- and subtype-specific recognition by antibody WF6 of a sequence segment forming an alpha-bungarotoxin binding site on the nicotinic acetylcholine receptor alpha subunit. Journal of Receptor Research 12(3): 299-321, 1992

Inward rectification of neuronal nicotinic acetylcholine receptors investigated by using the homomeric alpha 7 receptor. Proceedings. Biological Sciences 260(1358): 139-148, 1995

Identification of residues that confer alpha-conotoxin-PnIA sensitivity on the alpha 3 subunit of neuronal nicotinic acetylcholine receptors. Journal of Pharmacology and Experimental Therapeutics 306(2): 664-670, 2003

Iodo-alpha-conotoxin MI selectively binds the alpha/delta subunit interface of muscle nicotinic acetylcholine receptors. Biochemistry 43(21): 6656-6662, 2004

Substituents in the alpha subunit of nicotinic acetylcholine receptor which dictate alpha-conotoxin M1 binding. FASEB Journal 10(3): A688, 1996