Artículos de revistas
Molecular determinants of binding of a wasp toxin (PMTXs) and its analogs in the Na+ channels proteins
Fecha
2000-05-05Registro en:
Neuroscience Letters. Clare: Elsevier Sci Ireland Ltd, v. 285, n. 1, p. 29-32, 2000.
0304-3940
10.1016/S0304-3940(00)01017-X
WOS:000087088600008
Autor
Jichi Med Sch
Universidade Estadual Paulista (Unesp)
Suntory Inst Bioorgan Res
Tokyo Univ Agr
Hiroshima Univ
Tokyo Metropolitan Inst Neurosci
Institución
Resumen
The structural specificity of alpha-PMTX, a novel peptide toxin derived from wasp venom has been studied on the neuromuscular synapse in the walking leg of the lobster. alpha-PMTX is known to induce repetitive action potentials in the presynaptic axon due to sodium channel inactivation. We synthesized 29 analogs of alpha-PMTX by substituting one or two amino acids and compared threshold concentrations of these mutant toxins for inducing repetitive action potentials. In 13 amino acid residues of alpha-PMTX, Arg-1, Lys-3 and Lys-12 regulate the toxic activity because substitution of these basic amino acid residues with other amino acid residues greatly changed the potency. Determining the structure-activity relationships of PMTXs will help clarifying the molecular mechanism of sodium channel inactivation. (C) 2000 Elsevier B.V. Ireland Ltd. All rights reserved.