甘蓝夜蛾几丁质酶基因cDNA序列的克隆与序列分析

昆虫几丁质酶在害虫生物防治中具有很大的发展潜力。以甘蓝夜蛾Mamestra brassicae L.预蛹期幼虫整个虫体为材料提取总RNA,利用RT-PCR和cDNA末端快速扩增技术(RACE),扩增得到其几丁质酶的cDNA序列。该序列含有2826个碱基,包括1个1689个碱基的开放阅读框,预测编码1个含562个氨基酸的多肽,分子量约为62.6kDa,等电点为5.30。推导得到的氨基酸序列含有2个N-位糖基化位点,22个O-位糖基化位点,氨基酸序列与其他昆虫,尤其是鳞翅目昆虫的几丁质酶高度同源。获得的甘蓝夜蛾几丁质酶基因cDNA序列已经登录GenBank并获得登录号FJ436415。

Molecular cloning and sequence analysis of chitinase cDNA from Mamestra brassicae

Insect chitinase has great potential in biological control of insect pests. Total RNA was isolated from the whole body of Mamestra brassicae L. At prepupal stage. The cDNA sequence was cloned by RT-PCR and rapid amplification of cDNA ends was conducted. The cDNA of 2 826 base pairs in length contained an open reading frame of 1 689 base pairs coding for a polypeptide of 562 araino acid residues with a predicted molecular weight of 62.6 kDa and pI 5.30. The deduced amino acid sequence of M. Brassicae chitinase was predicted using the software Prosite, which indicated that it has two putative N-glycosylation sites and twenty two putative O-glycosylation sites. The predicted protein shared extensive similarities with those from other insects, expecially the lepidopteran insects. The cDNA sequence has been deposited in GenBank with accession No. FJ436415.