中国明对虾精氨酸激酶与白斑综合征病毒结构蛋白VP31的作用初探

Preliminary study on the conjunction between arginine kinase of Fenneropenaeus chinensis and the structure proteins of white spot syndrome virus(WSSV)

白斑综合征病毒(white spot syndrome virus,WSSV)是危害对虾的主要病原,给全球水产养殖业带来了巨大经济损失。为研究阻断WSSV的途径,前期研究WSSV与宿主相结合的受体蛋白发现,白斑综合征病毒囊膜蛋白VP31可以与中国明对虾(Fenneropenaeus chinensis)精氨酸激酶(FcAK)发生结合作用。精氨酸激酶(AK)通过调节无脊椎动物体内磷酸精氨酸与三磷酸腺苷(ATP)之间平衡在能量代谢、储存和利用方面具有重要作用。作者通过重组表达的rFcAK与rVP31的far-Western blotting分析,证实两者有结合作用,此外,rFcAK还与WSSV的VP19、VP28等6种结构蛋白有结合作用。双向电泳分析观察到,rFcAK与rVP31的磷酸化反应后,rVP31部分发生pI降低现象,提示rVP31可能发生了磷酸化。生物信息学分析表明VP31存在21个精氨酸残基,FcAK具有12个精氨酸结合位点,这可能为VP31和FcAK的结合活性提供了靶位。为进一步研究WSSV与宿主结合机理及阻断感染的机制提供思路。

White spot syndrome virus（WSSV） is a major shrimp pathogen causing big economic losses all over the world. Inorder ro explore ways to block WSSV infection, we worked on WSSV-binding host receptor proteins,, and we found that envelope protein VP31 of WSSV was able to engage with arginine kinase of Fenneropenaeus chinensis（FcAK）. Arginine kinase（AK） plays important roles in the metabolism, storage and utilization of energy by regulation of the balance between phosphorylation of arginine and ATP in invertebrate. The present study proves the binding between the recombinant FcAK（rFcAK） and VP31（rVP31） using far-Western blotting. Furthermore, the far-Western blotting also showed that rFcAK was able to bind other 6 structural proteins of WSSV, including VP19 and VP28. Two-dimensional electrophoresis analysis showed that part of VP31 migrated to the spot with reduced pI after the in vitro phosphorylating incubation between rFcAK and rVP31, suggesting that the rVP31 might be phosphorylated. The bioinformatics analysis showed that VP31 had 21 arginine residents and FcAK had 12 arginine binding sites. They may provide the loci for the binding activity between VP31 and FcAK. We’ll further elucidate the underlying binding mechanism between WSSV and host, and try to find ways to block the infection of WSSV.