DELTA-ATRACOTOXINS FROM AUSTRALIAN FUNNEL-WEB SPIDERS COMPETE WITH SCORPION ALPHA-TOXIN BINDING ON BOTH RAT-BRAIN AND INSECT SODIUM-CHANNELS

Citation
Mj. Little et al., DELTA-ATRACOTOXINS FROM AUSTRALIAN FUNNEL-WEB SPIDERS COMPETE WITH SCORPION ALPHA-TOXIN BINDING ON BOTH RAT-BRAIN AND INSECT SODIUM-CHANNELS, FEBS letters, 439(3), 1998, pp. 246-252
Citations number
55
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biology,"Cell Biology",Biophysics
Journal title
ISSN journal
0014-5793
Volume
439
Issue
3
Year of publication
1998
Pages
246 - 252
Database
ISI
SICI code
0014-5793(1998)439:3<246:DFAFSC>2.0.ZU;2-6
Abstract
delta-Atracotoxins are novel peptide toxins from the venom of Australi an funnel-web spiders that slow sodium current inactivation in a simil ar manner to scorpion alpha-toxins, To analyse their interaction with known sodium channel neurotoxin receptor sites we determined their eff ect on scorpion toxin, batracbotoxin and saxitoxin binding, Nanomolar concentrations of delta-atracotoxin-Hvl, and delta-atracotoxin-Ar1 com pletely inhibited the binding of the scorpion alpha-toxin AaH II to ra t brain synaptosomes as well as the binding of Lqh alpha IT, a scorpio n alpha-toxin highly active on insects, to cockroach neuronal membrane s. Moreover, delta-atracotoxin-Hv1 cooperatively enhanced batrachotoxi n binding to rat brain synaptosomes in an analogous fashion to scorpio n alpha-toxins. Thus the delta-atracotoxins represent a new class of t oxins which bind to both mammalian and insect sodium channels at sites similar to, or partially overlapping with, the receptor binding sites of scorpion alpha-toxins. (C) 1998 Federation of European Biochemical Societies.