Functional Peroral Infectivity Complex of White Spot Syndrome Virus of Shrimp
Functional Peroral Infectivity Complex of White Spot Syndrome Virus of Shrimp
复制标题
DOI：
10.1128/jvi.01173-22
复制
发表时间：
2022-12-21
影响因子：
5.4
通讯作者：
Hu, Zhihong
中科院分区：
文献类型：
--
作者：
Wang, Xi;Chen, Cheng;Hu, Zhihong
白斑综合征病毒（WSSV）是世界范围内对虾养殖疾病的主要原因。这种大型环状双链DNA病毒的感染过程已经得到了很好的研究，但其进入机制仍存在争议。主要的病毒粒子包膜蛋白VP28与虾的口腔和全身病毒感染有关。然而，对病毒DNA的遗传分析表明，杆状病毒中存在一些与PIF复合体蛋白相关的基因。这种复合体对于杆状病毒（大型陆生环状DNA病毒）进入昆虫幼虫的中肠上皮细胞至关重要。在这项研究中，我们旨在确定PIF复合物是否存在于WSSV中，该复合物的组成，它是否作为虾的口腔感染复合物，以及在海洋环境中促进其功能的生化特性。结果显示，WSSV PIF复合物（类似于720 kDa）包含至少8个蛋白，其中4个未被鉴定为PIF同源物：WSV134、VP124 （WSV216）、WSSV021和WSV136。由于预测的结构相似性和氨基酸序列相同，WSV134被认为是PIF4的同源物。WSSV - PIF复合物耐碱、蛋白水解和高盐，这些特性对于在水生环境中保持传染性很重要。口腔感染可以被pif特异性抗体中和，而不能被vp28特异性抗体中和。这些结果表明，WSSV PIF复合体对WSSV进入虾体至关重要；本文还讨论了该复合体的进化意义。白斑病是由白斑综合征病毒（WSSV）引起的，是世界范围内养殖对虾生产设施的主要祸害。这种疾病只有通过卫生设施才能得到有效控制。干预战略是迫切需要的，但由于缺乏适当的目标而受到限制。我们鉴定出的PIF复合物是WSSV进入虾体内的关键，可以为基于抗体或dsrna的干预策略提供新的靶点。此外，在WSSV中存在至少8个组分的PIF复合体，这与无脊椎杆状病毒的PIF复合体有祖先关系，表明该复合体在不同的病毒分类群中在结构和功能上是保守的。
White spot syndrome virus (WSSV) is a major cause of disease in shrimp cultures worldwide. The infection process of this large circular double-stranded DNA virus has been well studied, but its entry mechanism remains controversial. The major virion envelope protein VP28 has been implicated in oral and systemic viral infection in shrimp. However, genetic analysis of viral DNA has shown the presence of a few genes related to proteins of per os infectivity factor (PIF) complex in baculoviruses. This complex is essential for the entry of baculoviruses, large terrestrial circular DNA viruses, into the midgut epithelial cells of insect larvae. In this study, we aimed to determine whether a PIF complex exists in WSSV, the components of this complex, whether it functions as an oral infectivity complex in shrimp, and the biochemical properties that contribute to its function in a marine environment. The results revealed a WSSV PIF complex (similar to 720 kDa) comprising at least eight proteins, four of which were not identified as PIF homologs: WSV134, VP124 (WSV216), WSSV021, and WSV136. WSV134 is suggested to be a PIF4 homolog due to predicted structural similarity and amino acid sequence identity. The WSSV PIF complex is resistant to alkali, proteolysis, and high salt, properties that are important for maintaining infectivity in aquatic environments. Oral infection can be neutralized by PIF-specific antibodies but not by VP28-specific antibodies. These results indicate that the WSSV PIF complex is critical for WSSV entry into shrimp; the complex's evolutionary significance is also discussed.IMPORTANCE White spot disease, caused by the white spot syndrome virus (WSSV), is a major scourge in cultured shrimp production facilities worldwide. This disease is only effectively controlled by sanitation. Intervention strategies are urgently needed but are limited by a lack of appropriate targets. Our identification of a per os infectivity factor (PIF) complex, which is pivotal for the entry of WSSV into shrimp, could provide new targets for antibody- or dsRNA-based intervention strategies. In addition, the presence of a PIF complex with at least eight components in WSSV, which is ancestrally related to the PIF complex of invertebrate baculoviruses, suggests that this complex is structurally and functionally conserved in disparate virus taxa.