| Literature DB >> 2441741 |
B M Olivera, L J Cruz, V de Santos, G W LeCheminant, D Griffin, R Zeikus, J M McIntosh, R Galyean, J Varga, W R Gray.
Abstract
The omega-conotoxins from the venom of fish-hunting cone snails are probably the most useful of presently available ligands for neuronal Ca channels from vertebrates. Two of these peptide toxins, omega-conotoxins MVIIA and MVIIB from the venom of Conus magus, were purified. The amino acid sequences show significant differences from omega-conotoxins from Conus geographus. Total synthesis of omega-conotoxin MVIIA was achieved, and biologically active radiolabeled toxin was produced by iodination. Although omega-conotoxins from C. geographus (GVIA) and C. magus (MVIIA) appear to compete for the same sites in mammalian brain, in amphibian brain the high-affinity binding of omega-conotoxin MVIIA has narrower specificity. In this system, it is demonstrated that a combination of two omega-conotoxins can be used for biochemically defining receptor subtypes and suggested that these correspond to subtypes of neuronal Ca2+ channels.Entities:
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Year: 1987 PMID： 2441741 DOI： 10.1021/bi00382a004
Source DB: PubMed Journal: Biochemistry ISSN： 0006-2960 Impact factor: 3.162