一个东亚钳蝎蝎毒素BmTXKβ基因的克隆及其基因表达调控  

Genomic Cloning, Gene Expression and Regulation of a K^+ Blocking- peptide BmTXKβ from Chinese Scorpion Buthus martensii Karsch

作　　者：曹志贱[1] 肖帆[1] 毛歆[1] 刘辉[1] 李文鑫[1] 

机构地区：[1]武汉大学生命科学学院生物技术系,武汉430072

出　　处：《中国生物化学与分子生物学报》2002年第6期679-683,共5页Chinese Journal of Biochemistry and Molecular Biology

基　　金：国家自然科学基金 (No .3 9970 897)资助项目

摘　　要：从东亚钳蝎 (ButhusmartensiiKarsch ,BmK)毒腺组织cDNA文库中分离的长链钾通道毒素BmTXKβcDNA序列 ,克隆了BmTXKβ基因组序列 .BmTXKβ基因含有一个长度为 886bp的内含子 ,定位于BmTXKβ成熟肽中 ,与其它蝎毒素基因内含子定位于信号肽的基因结构不同 .并且 ,BmTXKβ基因的内含子特征也与其它蝎毒素基因不同 .研究结果从基因水平上证实了BmTXKβ是一个新的蝎毒素样肽 .以BmTXKβcDNA序列为探针与蝎基因组DNASouthern杂交出现 2条特异性杂交带 .杂交结果为蝎毒素基因可能通过DNA重排、多拷贝或多基因家族来调控基因表达提供了证据 .Genomic sequence of a long chain K + toxin BmTXKβ was cloned on the base of the full length cDNA sequence of BmTXK β isolated from BmK venom gland cDNA library. Analysis of nucleotide sequence showed that the region encoding mature peptide of BmTXKβ was disrupted by an intron with 886 bp,which was different from any other scorpion toxin gene with their introns within the signal peptide coding region. Moreover, the characteristics of this intron are different from those of other scorpion toxin genes described previously. These results indicate that BmTXKβ is a new member of the long chain K + scorpion toxin family at the gene level. Southern hybridization of the scorpion genome total DNA was performed using the full length cDNA sequence of BmTXK β as probe by a random priming radiolabelled procedure. Southern hybridization analysis showed that there were two specific hybridization signals, which indicated that scorpion regulated the expression of toxin genes using the mechanism of DNA rearrangement,multicopy or multiple gene family.

关 键 词：东亚钳蝎 蝎毒素 BmTXKβ基因 克隆 基因表达调控 

分 类 号：Q78[生物学—分子生物学] R996.3[医药卫生—毒理学]