1dg2

Publication Abstract from PubMed

The neuronal nicotinic acetylcholine receptors constitute a highly diverse group, with subtypes consisting of pentameric combinations of alpha and beta subunits. alpha-Conotoxins are a homologous series of small peptides that antagonize these receptors. We present the three-dimensional solution structure of alpha-conotoxin AuIB, the first 15-residue alpha-conotoxin known to selectively block the alpha(3)beta(4) nicotinic acetylcholine receptor subtype. The pairwise backbone and heavy-atom root mean square deviation for an ensemble of 20 structures are 0.269 and 0.720 A, respectively. The overall fold of alpha-conotoxin AuIB closely resembles that of the alpha4/7 subfamily alpha-conotoxins. However, the absence of Tyr(15), normally present in other alpha4/7 members, results in tight bending of the backbone at the C terminus and effectively renders Asp(14) to assume the spatial location of Tyr(15) present in other neuronal alpha4/7 alpha-conotoxins. Structural comparison of alpha-conotoxin AuIB with the alpha(3)beta(2) subtype-specific alpha-conotoxin MII shows different electrostatic surface charge distributions, which may be important in differential receptor subtype recognition.

Nuclear magnetic resonance solution conformation of alpha-conotoxin AuIB, an alpha(3)beta(4) subtype-selective neuronal nicotinic acetylcholine receptor antagonist.,Cho JH, Mok KH, Olivera BM, McIntosh JM, Park KH, Han KH J Biol Chem. 2000 Mar 24;275(12):8680-5. PMID:10722709^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.