家福捕鸟蛛毒素-22钠通道活性与基本性质分析  

An Analysis of Sodium Channel Activityand Basic Properties of the Jiafu Toxin-22 from S.jiafu Venom

作　　者：胡朝暾 周爱芳[1,2] 戴柏倩 于梦婷 HU Zhao-tun;ZHOUAi-fang;DAI Bo-qian;YU Meng-ting(Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province,Huaihua University,Huaihua,Hunan 418008;College of Biological and Food Engineering,Huaihua University,Huaihua,Hunan 418008)

机构地区：[1]怀化学院生物与食品工程学院,湖南怀化418008 [2]怀化学院民族药用植物资源研究与利用湖南省重点实验室,湖南怀化418008

出　　处：《怀化学院学报》2021年第5期39-44,共6页Journal of Huaihua University

基　　金：湖南省教育厅一般项目“家福捕鸟蛛毒腺转录组研究”(18C0978);湖南省自然科学基金面上项目“钩藤碱抑制Kv7.1通道的分子机制及应用研究”(2021JJ30540).

摘　　要：家福捕鸟蛛(Selenocosmia jiafu,S.jiafu)是一种生活在中国广西、云南等地的蜘蛛新种.研究发现其粗毒对大鼠背根神经节(Rat dorsal root ganglion,DRG)细胞河豚毒素不敏感型钠通道(tetrodotoxin-resistant,TTX-R)具有抑制作用.为了筛选得到抑制TTX-R活性的毒素分子,经反相高效液相色谱,从家福捕鸟蛛粗毒中分离得到1种新的毒素分子,命名为家福捕鸟蛛毒素-22(Jiafu toxin-22,JFTX-22).MALDI-TOF质谱分析和氨基酸序列分析表明该多肽毒素分子量为2807.227 Da,全序列为RCLPSGKACAGVTQK IPCCGSCVRGKCS.全细胞膜片钳分析表明JFTX-22对DRG细胞TTX-R通道具有抑制作用.此外,采用生物信息学方法初步分析了JFTX-22的基本理化性质、空间结构预测和同源序列比对等.结果表明JFTX-22的全长cDNA为471bp,编码一个65个氨基酸残基多肽.JFTX-22的二级结构主要以无规卷曲为主,其空间结构主要包含无规卷曲和三段反平行beta-折叠.同源序列比对发现JFTX-22跟Covalitoxin-I序列完全一致,与另外三种蜘蛛毒素JZTX-51、U1-theraphotoxin-Pf3和HWTX-X同源性较高.结果表明JFTX-22是一种潜在的具有镇痛活性的新型毒素分子.S.jiafu is recently identified as a new species of spider in Yunnan and Guangxi.It was found that the crude venom of the S.jiafu could inhibit TTX-R sodium channels in DRG ganglion neurons as revealed by voltage-clamp analysis.In order to screen for inhibitors from the crude venom of the S.jiafu,a novel neuron toxin,named Jiafu toxin-22(JF-22),was purified from the crude venom of the spider S.jiafu by reversed phase HPLC.The molecular weight of the toxin is 2807.227 Da determined by the analysis of MALDI-TOF mass analysis and the sequence is RCLPSGKACAGVTQKIPCCGSCVRGKCS determined by the amino acid sequence analysis.Whole cell patch clamp analysis showed that JFTX-22 has an inhibitory effect on the TTX-R channel of DRG cells.In addition,the basic physical and chemical properties,spatial structure prediction and homologous sequence comparison of JFTX-22 were analyzed using bioinformatics methods.The results show that the full-length cDNA of JFTX-22 is 471 bp,which encodes a 65 amino acid residue peptide.The secondary structure of JFTX-22 is mainly random coils and its spatial structure mainly includes random coils and three antiparallel beta-folds.The homologous sequence comparison revealed that JFTX-22 is completely identical with the Covalitoxin-I sequence,and has high homology with the other three spider toxins JZTX-51,U1-theraphotoxin-Pf3 and HWTX-X.The results indicate that JFTX-22 is a potential new toxin molecule with analgesic activity.

关 键 词：家福捕鸟蛛 家福捕鸟蛛毒素-22 全细胞膜片钳 钠通道活性 

分 类 号：Q78[生物学—分子生物学]