菜花烙铁头蛇毒C-型凝集素基因的克隆与序列分析

Cloning of cDNA Encoding a C-type Lectin from Snake Trimeresurus jerdonii

摘要: 从菜花烙铁头蛇(Trimeresurus jerdonii)的毒腺中提取mRNA，采用RT-PCR技术进行体外扩增，将扩增产物克隆到PMD18-T载体中，最后筛选出一个编码凝集素的基因，命名为TJL。由TJL基因序列推导的氨基酸序列中包含分别由23和135个氨基酸残基组成的信号肽和成熟肽。氨基酸序列比较分析表明，TJL含有半乳糖结合位点和钙离子结合位点，与蝰科蛇毒凝集素TSL、PAL、APL和RSL的同源性较高(87.4%-90.4%)，与眼镜蛇科蛇毒凝集素BML的同源性较低(61.5%)

Abstract: Total mRNA was extracted from the venom glands of snakes Trimeresurus jerdonii.The cDNAs encoding lectin were amplified by RT-PCR and cloned into PMD18-T vector.The positive clones encoding lectin were selected and sequenced,and was named TJL.The deduced amino acid sequence contains 135 residues,preceded by a signal peptide of 23 residues,including a galactose-binding site and a Ca2+ binding site.This C-type lectin shows great similarity to ones from Viperidae venoms and less similarity to one from Elapidae venom.