云南双生病毒优势种PaLCuCNV与介体烟粉虱互作研究

Geminiviruses are plant viruses with circular, single-stranded DNA genomes, which occur worldwide and cause significant damage in economic crops of tropical and subtropical regions. Papaya leaf curl China virus (PaLCuCNV) is a predominant geminivirus species in Yunnan. This plant disease epidemic has occurred in many areas of Yunnan, causing severe damage to tomato and pepper crops. PaLCuCNV is transmitted by the insect vector, Bemisia tabaci. B. tabaci is a cryptic species complex. Previous studies revealed that three B. tabaci species, invasive B cryptic species, Q cryptic species and indigenous cryptic species Asia I are the predominant whitefly species in Yunnan. This project will be to evaluate the interactions between PaLCuCNV and three B. tabaci species. The best PaLCuCNV-B. tabaci cryptic species interaction will be explicit. Namely, which is the best transmitter of PaLCuCNV will be detected. The transcriptome analysis will be conducted to compare this B. tabci species under the viruliferous and nonviruliferous conditions. After checking the datasheet, those genes exhibit significant differential expressions will be calculated. The significant differential pathways also will be analyzed. The objective is to reveal underlying molecular mechanisms of that insect vector adapts to plant virus, and to provide theory evidence to effectively control the epidemic of PaLCuCNV disease in Yunnan. Furthermore, it provides a solid foundation for further study on the mechanisms of vector Bemisia tabaci- PaLCuCNV, and for the new plant disease control strategy which aim to interdict B. tabaci to transmit the PaLCuCNV particles.

双生病毒是世界范围内广泛发生的一类植物单链DNA病毒，严重危害热带、亚热带多种经济作物。中国番木瓜曲叶病毒（PaLCuCNV）为云南双生病毒优势种，在多个区域暴发流行，严重影响番茄、辣椒种植。PaLCuCNV由烟粉虱传播。烟粉虱是一个隐种复合种。前期研究明确云南烟粉虱优势种为入侵B隐种、Q隐种和土著Asia I隐种烟粉虱。本项目拟通过对PaLCuCNV与三种烟粉虱互作比较，明确PaLCuCNV和烟粉虱互作效能最佳组合，即找出高效传播PaLCuCNV的隐种烟粉虱，并对该隐种进行带病毒和不带病毒的转录组研究，分析差异表达基因和代谢路径，揭示该隐种烟粉虱相适应传播PaLCuCNV的分子机制。为PaLCuCNV在云南快速发生、流行的有效防控提供依据，并为PaLCuCNV与介体烟粉虱更深层次的分子机理互作研究，乃至为以阻断烟粉虱对PaLCuCNV病毒粒子传播为靶标的新型病毒病防治策略打下坚实基础。

本项目针对云南烟粉虱隐种优势种（入侵B隐种、入侵Q隐种烟粉虱和Asia I隐种烟粉虱）与云南双生病毒优势种（中国番木瓜曲叶病毒，PaLCuCNV）开展互作研究，明确了B隐种、Q隐种、Asia I隐种烟粉虱对PaLCuCNV的获毒能力差异不显著，但持毒能力与传播效率以B隐种烟粉虱为最好。B隐种、Q隐种和Asia I隐种烟粉虱在健康番茄和感病番茄品种上种群增长种内差异不明显，种间差异大，以Q隐种烟粉虱在带毒番茄上的种群增长表现为最好，三种烟粉虱对带毒和健康番茄品种未显示出明显选择性偏好。对B隐种、Q隐种和Asia I隐种烟粉虱在带毒和不带毒情况下的转录组比较研究发现，入侵烟粉虱隐种B和Q隐种在健康和携带PaLCuCNV的差异表达基因，显著比Asia I差异表达基因多，说明入侵隐种可能通过调节自身基因的表达可更好的适应带毒状态下的生存。对B隐种与PaLCuCNV互作的差异表达基因pathway富集分析，发现所有差异基因富集到了249条通路上。经过筛选，推测MARK信号通路、mTOR、RAS等通路在参与获毒、持毒、传毒以及自身对病毒的免疫反应方面扮演着重要的作用，值得后续深入研究，可望找到抑制烟粉虱传播PaLCuCNV的重要靶标基因。田间调查研究表明，PaLCuCNV在云南发生、流行与B隐种烟粉虱的发生密切相关，局部区域随着发生B隐种被Q隐种烟粉虱取代，PaLCuCNV的发生危害大幅减弱，B隐种烟粉虱与PaLCuCNV为最佳效能组合。. 本项目的研究为揭示PaLCuCNV在云南快速发生、流行的机制与有效防控提供了理论参考，且为下一步深入研究打下基础。本项目已发表论文4篇，其中SCI论文3篇，项目主持人晋升正高级专业学术职称，获得“西部之光”访问学者荣誉称号，并通过云南省中青年学术与技术带头人出站评价。