织锦芋螺ο家族芋螺毒素的序列分析

Cloning of ο-Family Conotoxin Sequances from Conus textile Verom Duct

为了从织锦芋螺（Ｃｏｎｕｓｔｅｘｔｉｌｅ）中尽可能多地分离出ο家族的毒素序列和研究其应用价值，在克隆了织锦芋螺α芋螺毒素的基础上进行了织锦芋螺ο家族芋螺毒素基因的分离工作．从织锦芋螺毒管中提取ｍ ＲＮＡ，通过ＲＡＣＥ（ｒａｐｉｄ ａｍ ｐｌｉｆｉｃａｔｉｏｎ ｏｆｃＤＮＡ ｅｎｄｓ，ｃＤＮＡ 末端的快速扩增）－ＰＣＲ方法扩增获得ο家族芋螺毒素ｃＤＮＡ 片段，并进行克隆和序列分析．从织锦芋螺毒液中获得了６种新的芋螺毒素序列，且毒素序列的成熟肽部分均符合Ｃ－ Ｃ－ ＣＣ－ Ｃ－ Ｃ的保守半胱氨酸框架．这些是新的ο家族芋螺毒素序列，新序列的阐明为进一步研究其生物活性和应用打下了基础．

Omega conotoxins are specific blocks of voltage sensitive calcium channels,and a group of most important toxins of conotoxins.Recent studies have found that there are more than ten small peptides with biological activity from Conus textile venom duct.But,only several of them have been sequenced.Objective is to obtain new conotoxin sequences from Conus textile picked from south ocean of our country and study the potential usage of conotoxin.Using primers corresponding to conserved signal peptide coding region and oligo(dT) which bound to the poly(A) tracts on eukaryotic mRNA,and omega conotoxin coding cDNA was RACE PCR amplificated.Six new conotoxin sequences were found.The predicted mature peptide sequences belonged to conserved cysteine frame:C C CC C C. A number of new conotoxins were sequenced and this set the foundation for further investigating their biological activity and application.