Abstract: The invention is directed to A-lineage conotoxin peptides, which are conotoxin peptides that have strong homology in the signal sequence and the 3'-untranslated region of the genes coding for these peptides to the sequences in the .alpha.-conotoxin peptides. The A-lineage conotoxin peptides include the .alpha.-conotoxin peptides, the .alpha.-conotoxin-like peptides and the .kappa.-conotoxin peptides, described further below. The .alpha.-conotoxin-peptides generally share a "core" sequence motif. This core sequence is termed the .alpha.3/5 core and is represented as Cys-Cys-Xaa-Xaa-Xaa- Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO:1). The .alpha.-conotoxin-like peptides generally share a core sequence termed the .alpha.4/7 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Xaa-Cys-Xaa- Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO:2). The .kappa.-conotoxin peptides generally have a core sequence termed the .kappa.

Abstract: The invention is directed to A-lineage conotoxin peptides, which are conotoxin peptides that have strong homology in the signal sequence and the 3'-untranslated region of the genes coding for these peptides to the sequences in the .alpha.-conotoxin peptides. The A-lineage conotoxin peptides include the .alpha.-conotoxin peptides, the .alpha.-conotoxin-like peptides and the .kappa.-conotoxin peptides, described further below. The .alpha.-conotoxin-peptides generally share a "core" sequence motif. This core sequence is termed the .alpha.3/5 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO: 1). The .alpha.-conotoxin-like peptides generally share a core sequence termed the .alpha.4/7 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO:2). The .kappa.-conotoxin peptides generally have a core sequence termed the .kappa.

Abstract: The invention is directed to A-lineage conotoxin peptides, which are conotoxin peptides that have strong homology in the signal sequence and the 3'-untranslated region of the genes coding for these peptides to the sequences in the .alpha.-conotoxin peptides. The A-lineage conotoxin peptides include the .alpha.-conotoxin peptides, the .alpha.-conotoxin-like peptides and the .kappa.-conotoxin peptides, described further below. The .alpha.-conotoxin-peptides generally share a "core" sequence motif. This core sequence is termed the .alpha. 3/5 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO: 1). The .alpha.-conotoxin-like peptides generally share a core sequence termed the .alpha. 4/7 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO: 2). The .kappa.-conotoxin peptides generally have a core sequence termed the .kappa.

Abstract: The invention is directed to A-lineage conotoxin peptides, which are conotoxin peptides that have strong homology in the signal sequence and the 3'-untranslated region of the genes coding for these peptides to the sequences in the .alpha.-conotoxin peptides. The A-lineage conotoxin peptides include the .alpha.-conotoxin peptides, the .alpha.-conotoxin-like peptides and the .kappa.-conotoxin peptides, described further below. The .alpha.-conotoxin-peptides generally share a "core" sequence motif. This core sequence is termed the .alpha.3/5 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO:1). The .alpha.-conotoxin-like peptides generally share a core sequence termed the .alpha.4/7 core and is represented as Cys-Cys-Xaa-Xaa-Xaa-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Xaa-Cys (SEQ ID NO:2). The .kappa.-conotoxin peptides generally have a core sequence termed the .kappa.

Abstract: Substantially pure conotoxins are provided which inhibit synaptic transmissions at the neuromuscular junctions and which are useful both in vivo and in assays because they specifically target particular receptors, such as the acetylcholine receptor, and ion channels. The peptides are of such length that they can be made by chemical synthesis. They also may be made using recombinant DNA techniques, and the DNA encoding such conotoxins having pesticidal properties can be incorporated as plant defense genes into plant species of interest.

Abstract: The present invention provides bioactive peptides of generic formula ##STR1## These peptides are extremely potent inhibitors of synaptic transmission at the neuromuscular junction, while at the same time lacing demonstrable inhibition of either nerve or muscle action potential propagation. The peptides are termed conotoxins herein. Naturally occurring conotoxins include conotoxin GI, GIA and GII. In conotoxin GI, U is Glu, V.sub.4 is Asn, V.sub.5 is Pro, V.sub.6 is Ala, W is Gly, X is Arg, Y is His, Z is Tyr, V.sub.12 is Ser and R is --NH.sub.2. Conotoxin GIA is identical to GI except R is --Gly--Lys--NH.sub.2. Conotoxin GII is identical to GI except that V.sub.4 is His, Z is Phe, and X is Lys. Conotoxin MI is identical to GI except that U is Gly-Arg, X is Lys and Y is Asn.