家蚕谷胱甘肽转移酶基因的克隆、序列分析及其表达模式  

Cloning,Sequcene Analysis and Expression Pattern of Glutathione S-transferase Gene in Bombyx mori

作　　者：左伟东[1] 余泉友[1] 李斌[1] 刘志[1] 代方银[1] 鲁成[1] 

机构地区：[1]西南大学农业部蚕桑学重点实验室,重庆400715

出　　处：《农业生物技术学报》2007年第4期595-601,共7页Journal of Agricultural Biotechnology

基　　金：国家重点基础研究发展规划(973)项目(No.2005CB121004);科技部国家攻关项目(No.2005BA711A07);国家自然科学基金(No.30300262)资助

摘　　要：谷胱甘肽-S-转移酶(GSTs)是昆虫体内重要的解毒酶系,在对外源和内源化合物解毒代谢中起着重要的作用。以GenBank中已知的昆虫GST的氨基酸序列在家蚕(Bombyx mori)基因组序列中作TBLASTN检索,获得了多个可能的家蚕GST同源基因。对其中的一个GST新基因进行了EST分析和克隆,结果表明,该基因编码区全长663bp。以该基因推导的氨基酸序列与其它物种的GSTs进行相似性比较和系统发育分析,发现此基因为delta家族的成员,并命名为BmGSTd3。RT-PCR结果表明,BmGSTd3基因在家蚕5龄第3天的8个组织中都有表达,中肠和表皮的表达丰度较高。在辛硫磷处理家蚕后的72h内,BmGSTd3基因的转录水平与对照组相比没有显著的变化。对BmGSTd3基因的5'侧翼区的调控序列进行了预测,共发现12个可能与内源和外源物代谢以及抗氧化相关的转录调控元件。Glutathione S-transferases （GSTs） play a central role in detoxication ofxenobiotic and endogenous compounds in insect. The amino acid sequences of insect GSTs were downloaded from GenBank, and used to search the silkworm （Bombyx mori） genome sequences by TBLASTN program. Many putative GST genes were found in silkworm genome. One new GST gene was chosen by ESTs analysis and then cloned from the cDNA of silkworm fat body. The results indicated that the complete coding sequence was 663 bp. Based on the phylogenetic tree and sequence similarities, the silkworm GST might belong to the delta family, and named as BmGSTd3. RT-PCR results showed that the BmGSTd3 expressed in eight tissues of the 3rd day of 5th instar silkworm, but its expression was higher in midgnt and epidermis. After the silkworm exposed to phoxim, the transcription level of BmGSTd3 did not change significantly. In addition, 5′-flanking region of BmGSTd3 was used to predict the transcription regulatory elements and 12 elements in total were found,which are related to detoxification of endogenous, exogenous compounds and antioxidant role.

关 键 词：家蚕 谷胱甘肽-S-转移酶 序列分析 表达模式 

分 类 号：S188[农业科学—农业基础科学]