PDF(Pubmed)
Abstract：
Throughout evolution, arboviruses have developed various strategies to counteract the host\'s innate immune defenses to maintain persistent transmission. Recent studies have shown that, in addition to bacteria and fungi, the innate Toll-Dorsal immune system also plays an essential role in preventing viral infections in invertebrates. However, whether the classical Toll immune pathway is involved in maintaining the homeostatic process to ensure the persistent and propagative transmission of arboviruses in insect vectors remain unclear. In this study, we revealed that the transcription factor Dorsal is actively involved in the antiviral defense of an insect vector (Laodelphax striatellus) by regulating the target gene, zinc finger protein 708 (LsZN708), which mediates downstream immune-related effectors against infection with the plant virus (Rice stripe virus, RSV). In contrast, an antidefense strategy involving the use of the nonstructural-protein (NS4) to antagonize host antiviral defense through competitive binding to Dorsal from the MSK2 kinase was employed by RSV; this competitive binding inhibited Dorsal phosphorylation and reduced the antiviral response of the host insect. Our study revealed the molecular mechanism through which Toll-Dorsal-ZN708 mediates the maintenance of an arbovirus homeostasis in insect vectors. Specifically, ZN708 is a newly documented zinc finger protein targeted by Dorsal that mediates the downstream antiviral response. This study will contribute to our understanding of the successful transmission and spread of arboviruses in plant or invertebrate hosts.
摘要：
在整个进化过程中,虫媒病毒已经开发了各种策略来对抗宿主的先天免疫防御，以维持持续的传播。最近的研究表明,除了细菌和真菌，先天的Toll-背侧免疫系统在预防无脊椎动物病毒感染方面也起着重要作用。然而,经典的Toll免疫途径是否参与维持体内平衡过程以确保虫媒病毒在昆虫载体中的持续和繁殖传播仍不清楚.在这项研究中,我们发现转录因子Dorsal通过调节靶基因积极参与昆虫载体（Laodelphoxstriatellus）的抗病毒防御，锌指蛋白708(LsZN708),介导下游免疫相关效应子抵抗植物病毒感染(水稻条纹病毒，RSV）。相比之下,RSV采用了一种抗防御策略，该策略涉及使用非结构蛋白（NS4）通过MSK2激酶与Dorsal的竞争性结合来拮抗宿主抗病毒防御；这种竞争性结合抑制了Dorsal磷酸化并降低了宿主昆虫的抗病毒反应。我们的研究揭示了Toll-Dorsal-ZN708介导维持昆虫载体中虫媒病毒稳态的分子机制。具体来说,ZN708是一种新记录的锌指蛋白，由Dorsal靶向，介导下游抗病毒反应。这项研究将有助于我们了解虫媒病毒在植物或无脊椎动物宿主中的成功传播和传播。
