桃蚜鞣化激素基因克隆与表达分析

Cloning and Expression of Bursicon Gene of Myzus persicae(Sulzer)

Bursicon是调节昆虫表皮硬化及展翅的激素类蛋白,它在昆虫表皮硬化和翅伸展过程中起着关键作用。本研究克隆获得桃蚜Bursicon基因(burs-α和burs-β)全长,分别命名为Mpburs-α(GenBank登录号:MF083566)和Mpburs-β(GenBank登录号:MF083567)。Mpburs-α开放阅读框长483bp,编码160个氨基酸。其相对分子量为17.59kDa,分子式为C_(759)H_(1204)N_(210)O_(232)S_(19);理论等电点为7.96,Mpburs-β开放阅读框长417bp,编码138个氨基酸。其相对分子量为15.45kDa,分子式为C672H1072N180O212S12;理论等电点为4.84。分子系统进化树分析表明,桃蚜与豌豆蚜Acyrthosiphon pisum和麦双尾蚜Diuraphis noxia具有较近的亲缘关系。RT-qPCR结果表明:Mpburs-α和Mpburs-β在桃蚜各龄期均有表达,以1龄若蚜期表达量最高;成蚜有翅个体中表达量显著高于无翅个体。推测Bursicon在桃蚜翅的形成中发挥着重要作用。研究结果可为续研究Bursicon在桃蚜蜕皮后表皮的骨化、翅的形成方面相关的功能机制奠定基础。

Bursicon regulates the epidermal sclerosis and wing-spreading in insects. It plays a key role in epidermis hardening of insects after molting. The full-length sequences of the bursicon genes （burs-a and burs-β） of M. persicae （Sulzer） were obtained through cloning for this study, and named Mpburs-α （GenBank accession number： MF083566） and Mpburs-~ （GenBank accession number： MF083567）, respectively. Mpburs-α contained a 483 bp open reading frame （ORF） and was encoded 160 amino acid residues. Its molecular mass was predicted to be 17.59 kDa with a formula of Crs9 H1204 N210023z 819 and an isoelectric point of 7.96. Mpburs- contained a 417 bp ORF and was encoded 138 amino acids. Its molecular mass to be 15.45 kDa with a formula of C672 H1072 N180 O212S12 and an isoelectrie point of 4.8. The phylogenetie tree analysis showed a relatively close genetic relationship of M. persicae with Acyrthosiphon pisum （Harris） and Diuraphis noxia （Mordvilko）. The qRT-PCR results indicated that Mpburs-a and Mpburs-β expressed during the entire developmental stage of M. persicae and arrived at a peak expression level in the iSt instar nymph. The expression levels of the two genes in the winged adult aphids were significantly higher than those in the wingless adult aphids suggesting an important role played by bursicon in the wing development for the insect. The finding might lead to further studies on the functions of bursicon in the molting epidermal ossification and wing formation of M. persicae.