TZSV在两种传毒蓟马体内侵染循回途径差异机制的比较研究

The diseases caused by tospoviruses had lead to significant losses in crop production and quality worldwide. Tomato zonate spot virus (TZSV) is a new member of tospoviruses that was first reported in Yunnan province, China. It is the dominant species of the genus Tospovirus in Yunnan province and it has been causing substantial yield losses in vegetable, tobacco and other cash crops in recent years. Our previous work showed that F. occidentalis and T. palmi are the vectors of TZSV although the characteristics of the transmission of TZSV between them were significantly difference. Thus we speculated large field populations and high transmission capacity of F. occidentalis were key factors that caused widely prevalence of TZSV in fields. Based on our preliminary research, immunofluorescence technique was used to study the difference of the spreading routes of TZSV in the two thrips vectors, and Far western blot technique was used to search and analyze differential proteins related with transmission in the two thrips vectors. The results will provide a theory foundation for the new plant disease control strategy which aims to interdict thrips vectors to transmit the TZSV particles.

番茄斑萎病毒属病毒(Tospoviruses)在世界范围内分布广泛，引起多种作物的严重病害。番茄环纹斑点病毒(Tomato zonate spot virus, TZSV) 是近年来在云南发现的Tospoviruses一个新种，对番茄、辣椒等经济作物造成严重经济损失，并有向邻近省区蔓延的趋势。前期研究结果表明，西花蓟马和棕榈蓟马均可传播TZSV，但传毒特性有明显差异，因此推测，与TZSV高亲和性的西花蓟马田间种群大、传播TZSV的能力高是导致TZSV在田间广泛分布的关键因子。本项目拟在前期研究结果基础上，通过免疫荧光标记等方法，系统比较研究TZSV在西花蓟马、棕榈蓟马体内的侵染循回途径差异，通过Far western blot 技术分离鉴定影响这种差异的两种蓟马主要传毒相关蛋白的异同。研究结果可为设计阻断病毒突破传毒蓟马介体屏障、切断病毒在蓟马体内有效循回途径的新型病毒病防控策略奠定基础。

番茄环纹斑点病毒(Tomato zonate spot virus, TZSV) 在云南当地广泛发生，对番茄、辣椒等经济作物造成严重经济损失。项目组前期研究结果表明，西花蓟马和棕榈蓟马均可传播TZSV，但传毒特性有明显差异。本项目研究发现西花蓟马对TZSV获毒能力高于棕榈蓟马；利用激光共聚焦显微镜、透射电子显微镜、免疫荧光标记等方法，系统描述了西花蓟马和棕榈蓟马成虫消化道的组织学和形态学结构，发现西花蓟马和棕榈蓟马消化系统由前肠、中肠、后肠、唾液腺和马氏管构成，描绘了TZSV在西花蓟马、棕榈蓟马体内的分布、侵染循回途径差异，发现TZSV粒子未能突破棕榈蓟马前肠和中肠屏障；采用酵母双杂交技术筛选出与TZSV NSs蛋白互作的介体因子电压依赖性阴离子通道(voltage-dependent anion channels,VDAC)，为了验证蛋白互作真实性，通过GST pull-down技术检测到NSs蛋白与VDAC蛋白的混合样本检测到蛋白条带VDAC，体外验证了NSs蛋白与VDAC之间的相互作用，发现TZSV NSs与西花蓟马VDAC在体外存在相互作用。研究结果将为设计切断介体蓟马对TZSV病毒粒子传播为靶标的病害调控新策略奠定基础。项目执行期间，项目主持人完成云南省学术技术带头人后备人才培养，2019年入选云南省万人计划青年拔尖人才，发表论文8篇，指导2名硕士完成毕业论文。