Novel O-superfamily conotoxins identified by cDNA cloning from three vermivorous Conus species.
The O-superfamily of conotoxins includes several subfamilies with different pharmacological targets, all of which are voltage-gated ion channels and distributed widely in varied Conus species. The venom components from any Conus species are quite distinct from those of other species. Seven novel O-superfamily peptides were identified by cDNA cloning from the three vermivorous Conus species of C. betulinus, C. lividus and C. caracteristicus native to Hainan. They share three common signal sequences, and a conserved arrangement of cysteine residues (C-C-CC-C-C). Phylogenetic analysis of newly found conotoxins in this study and known homologue O-superfamily sequences from the other Conus species was performed systematically. Divergence and percentage identity of the amino acid sequences of the signal regions suggest that the novel conotoxins described in this investigation belong to the three broad clades: MSGL, ME-QK and MKLT, each of which has its own characteristic signature signal sequence and cysteine codon conservation. Relative to this work, it is noted that O-superfamily conotoxins are not well represented from vermivorous species. The elucidated cDNAs of these newly found vermivorous toxins would facilitate a better understanding for basic research and drug discovery.
Zhangsun
Dongting
D
Key Laboratory for Tropical Biology Resources (MOE), Ocean College, Center for Experimental Biotechnology, Hainan University, Haikou Hainan 570228, China.
Luo
Sulan
S
Wu
Yong
Y
Zhu
Xiaopeng
X
Hu
Yuanyan
Y
Xie
Lei
L
D000818:Animals; D003001:Cloning, Molecular; D020916:Conotoxins / Q000235:genetics / Q000302:isolation & purification*; D017124:Conserved Sequence; D052078:Conus Snail; D003545:Cysteine; D018076:DNA, Complementary; D010455:Peptides; D010802:Phylogeny; D021382:Protein Sorting Signals; D013045:Species Specificity
D020916:Conotoxins; D018076:DNA, Complementary; D010455:Peptides; D021382:Protein Sorting Signals; D003545:Cysteine