亚洲小车蝗痘病毒球状体蛋白基因的克隆与序列分析

Cloning and Analysis of Oedaleus asiaticus Entomopoxvirus Spheroidin Gene

通过PCR扩增,获得OaEPV球状体蛋白基因编码区序列,并进行克隆、测序。分析结果显示,OaEPV球状体蛋白基因编码区全长为2967bp,编码分子量为111kDa的球状体蛋白。同源性分析表明,OaEPV球状体蛋白基因与直翅目昆虫痘病毒关系最近,与鳞翅目和鞘翅目昆虫痘病毒关系较远。对已知的几种昆虫痘病毒球状体蛋白基因做系统进化树,结果显示,以病毒寄主的昆虫分类目作为昆虫痘病毒的分属依据,更符合分子水平的分析结果,也与近年来许多学者所提出的“将鳞翅目与直翅目昆虫痘病毒分为2个不同的属”的观点相一致。对这些球状体蛋白氨基酸序列的疏水性进行分析,表明球状体蛋白的疏水性随寄主昆虫所处的目不同而表现出较大差异,这可能是因为病毒与寄主长期的协同进化的结果。

The coding region of Oedaleus asiaticus EPV spheroidin gene was obtained by PCR, and this fragment was subsequently cloned, sequenced and analyzed. The data shows OaEPV sph coding region is 2967bp in size which encodes a 111 kDa protein. Homology analysis demonstrated that OaEPV is closer to Orthopteran EPVs than Lepidopteran and Coleopteran EPVs. Phylogenetic tree derived from all known EPVs spheroidin gene indicates that the order of the EPV host is in relationship with the genus of corresponding EPV, which agrees with a recent point that 'Lepidopteran EPVs and Orthopteran EPVs should be divided into two distinct genus'. Hydrophobicity plots of these known speroidin show that the more distant relationship of the orders the viruses hosts belong to, the more diverse of the property of EPV spheroidin to each other. It may be explained as the result of co-evolution between the EPVs and their host.