野桑蚕乳酸脱氢酶基因的克隆与表达分析

Cloning and Expression Profiling Analysis of Bombyx mandarina LDH Gene

为了研究野桑蚕乳酸脱氢酶基因的功能,选择野桑蚕5龄3日幼虫的组织及不同发育时期的个体,利用PCR技术对野桑蚕乳酸脱氢酶基因进行克隆,得到野桑蚕乳酸脱氢酶基因开放阅读框长度为996bp,没有内含子,只有1个外显子。该基因编码的蛋白含有331个氨基酸残基,等电点为6.76,分子量为36.35kD。氨基酸序列分析表明,该蛋白高度保守,亚细胞定位预测分析表明该蛋白主要定位于细胞质中。转录表达分析表明,该基因在野桑蚕5龄3日幼虫的组织(马氏管、中肠、表皮、脂肪体、丝腺、血液、精巢和卵巢)及不同发育时期的个体(卵、幼虫、蛹和蛾)中均有表达,且表达量趋于一致。表明乳酸脱氢酶基因在野桑蚕的生命活动中可能具有重要的生理功能。

In order to explore the functions of lactate dehydrogenase（LDH）,using the different tissues of 3 day of fifth instar larvae and the different developmental stages individuals,the LDH gene from Bombyx mandarina was cloned by polymerase chain reaction.The results showed that the open reading frame of LDH was 996 bp,encoding 331 amino acid,containing 1 exon,no intron,and a predicted pI of 6.76 and molecular weight of 36.35 kD.The deduced amino acid sequence was highly conserved.The predicted analysis showed that the LDH was located in the cytoplasm.Transcriptal expression pattern revealed that the LDH was expressed in the tissues （malpig-hian tubule,midgut,epidermis,fat body,silk gland,blood,testis,ovary ） and developmental stages（egg,larva,pupa,moth）,and the expression level was almost consistent. LDH may play an important physiological function in vital movement of Bombyx mandarina .