title: Two novel O-superfamily conotoxins from Conus vexillum.
abstract: O-superfamily conotoxins include several families that have diverse pharmacological activity on Na+, K+ or Ca2+ channels. These superfamily toxins have been mainly found in fish-hunting and mollusk-hunting Conus species. Here, we reported two novel O-superfamily conotoxins, vx6a and vx6b, purified from a worm-hunting cone snail, Conus vexillum. Though their cysteine framework and signal peptides share high similarity with those of other members of O-superfamily, the mature vx6a and vx6b both have a low sequence homology with others. To test the biological function of vx6a, the toxin was chemically synthesized and then tested on the locust dorsal unpaired median (DUM) neuron system which containing various ion channels. Although no any activity on ion channels was found on the DUM neuron system, vx6a could clearly elicit a series of symptoms in mouse via intracranial injection, such as quivering, climbing, scratching, barrel rolling and paralysis of limbs at different dose.
authors.affiliation: Key Laboratory of Proteomics, Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institute of Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.forename: Chen-Qi
authors.initials: CQ
authors.lastname: Xu
authors.forename: Cheng-Zhong
authors.initials: CZ
authors.lastname: Wang
authors.forename: Chong-Xu
authors.initials: CX
authors.lastname: Fan
authors.forename: Ting-You
authors.initials: TY
authors.lastname: Zhao
authors.forename: Ji-Sheng
authors.initials: JS
authors.lastname: Chen
authors.forename: Cheng-Wu
authors.initials: CW
authors.lastname: Chi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019976:Cloning, Organism; D020916:Conotoxins / Q000138:chemical synthesis / Q000302:isolation & purification / Q000633:toxicity*; D052078:Conus Snail; D004305:Dose-Response Relationship, Drug; D007473:Ion Channels / Q000187:drug effects*; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny
chemical_list: D020916:Conotoxins; D007473:Ion Channels