title: Discovery of a novel class of conotoxin from Conus litteratus, lt14a, with a unique cysteine pattern.
abstract: Conus litteratus is a worm-hunting cone snail with a highly sophisticated neuropharmacological defense strategy using small peptides in its venom. By analyzing different clones in the cDNA library of venom ducts from C. litteratus, we identified the peptide lt14a which displays a characteristic signal peptide sequence in its precursor and a unique arrangement of Cys residues (-C-C-C-C-) in its mature peptide region. RT-PCR analysis suggested that lt14a is abundantly expressed throughout the whole venom duct. An intensive analysis in sequence suggested that lt14a is similar to alpha-conotoxin qc1.1 cloned from Conus quercinus. We conducted the chemical synthesis of lt14a. The synthetic lt14a has a remarkable biological activity to suppress pain and inhibits the neuronal-type nicotinic acetylcholine receptors.
authors.affiliation: State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutic Functional Genes, The Open Laboratory for Marine Functional Genomics of State High-Tech Development Program, College of Life Sciences, Sun Yat-Sen University, Guangzhou, PR China.
authors.forename: Can
authors.initials: C
authors.lastname: Peng
authors.forename: Shaojun
authors.initials: S
authors.lastname: Tang
authors.forename: Canhui
authors.initials: C
authors.lastname: Pi
authors.forename: Junliang
authors.initials: J
authors.lastname: Liu
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Wenliang
authors.initials: W
authors.lastname: Zhou
authors.forename: Anlong
authors.initials: A
authors.lastname: Xu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001001:Anura; D001483:Base Sequence; D002478:Cells, Cultured; D020916:Conotoxins / Q000737:chemistry* / Q000145:classification / Q000494:pharmacology; D003545:Cysteine / Q000032:analysis*; D005260:Female; D051379:Mice; D008969:Molecular Sequence Data; D018733:Nicotinic Antagonists / Q000737:chemistry* / Q000494:pharmacology; D051381:Rats; D011978:Receptors, Nicotinic / Q000378:metabolism
chemical_list: D020916:Conotoxins; D018733:Nicotinic Antagonists; D011978:Receptors, Nicotinic; C514610:lt14a peptide, Conus litteratus; D003545:Cysteine