Cloning of novel O-superfamily conotoxin of Conus capitaneus collected from Hainan / 中国海洋药物

ABSTRACT

Objective To isolate and clone novel O-superfamily conotoxin genes of Conus capitaneus Linnaeus collected from Hainan,which would provide the initial drug leads to investigate and develop Conus capitaneus conotoxins.Methods 3'-RACE(Rapid Amplification of cDNA Ends) was used for cloning the novel O-superfamily conotoxins.The specific amplified cDNA fragments were sequenced and analyzed,as well as the genetic diversity of the O-superfamily conotoxins.Results The full-length cDNA(CaHr91N) of a new O-superfamily conotoxin(CaHr91) was cloned and sequenced from Conus capitaneus Linnaeus.The novel conotoxin precursor CaHr91P with 77 amino acids(aa) encoded by the cDNA consists of three typical regions of signal with 21aa, pro-peptide with 22aa and mature peptide with 34aa.Predicted sequence of the toxin region CaHr91M is "ECREQSQGC TNTSPPCC SGLRC SGQSQGGVC ISN" with a common O-superfamily cysteine pattern C-C-CC-C-C.Percent identities between CaHr91P and other published homologue O-superfamily sequences were compared systematically,as well as research status on conopeptides from C.capitaneus.Conlusion The elucidated cDNA of the novel CaHr91P conotoxin will be the basis for a better understanding of its bioactivity and application,as well as finding more novel conotoxins from C.capitaneus.