1m2c
From Proteopedia
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THREE-DIMENSIONAL STRUCTURE OF ALPHA-CONOTOXIN MII, NMR, 14 STRUCTURES
Overview
We have isolated a 16-amino acid peptide from the venom of the marine, snail Conus magus which potently blocks nicotinic acetylcholine receptors, (nAChRs) composed of alpha3beta2 subunits. This peptide, named, alpha-conotoxin MII, was identified by electrophysiologically screening, venom fractions against cloned nicotinic receptors expressed in Xenopus, oocytes. The peptide's structure, which has been confirmed by mass, spectrometry and total chemical synthesis, differs significantly from, those of all previously isolated alpha-conotoxins. Disulfide bridging, however, is conserved. The toxin blocks the response to acetylcholine in, oocytes expressing alpha3beta2 nAChRs with an IC50 of 0.5 nM and is 2-4, orders of magnitude less potent on other nAChR subunit combinations. We, have recently reported the isolation and characterization of, alpha-conotoxin ImI, which selectively targets homomeric alpha7 neuronal, nAChRs. Yet other alpha-conotoxins selectively block the muscle subtype of, nAChR. Thus, it is increasingly apparent that alpha-conotoxins represent a, significant resource for ligands with which to probe structure-function, relationships of various nAChR subtypes.
About this Structure
1M2C is a Single protein structure of sequence from Conus magus with NH2 as ligand. Full crystallographic information is available from OCA.
Reference
A new alpha-conotoxin which targets alpha3beta2 nicotinic acetylcholine receptors., Cartier GE, Yoshikami D, Gray WR, Luo S, Olivera BM, McIntosh JM, J Biol Chem. 1996 Mar 29;271(13):7522-8. PMID:8631783
Page seeded by OCA on Tue Nov 20 21:05:06 2007
Categories: Conus magus | Single protein | Koerber, S.C. | Mcintosh, J.M. | Olivera, B.M. | Rivier, J.E. | Shon, K.J. | NH2 | Cholinergic modulation | Dopamine release | Neuronal nicotinic acetylcholine receptor inhibitor | Neurotoxin | Presynaptic nicotinic acetylcholine receptor blocker | Subtype specific ligand
