Laboratory of Plant Virology, Department of Biological Sciences, Faculty of Agriculture, Saga University, 840-8502 Saga, Japan;
Published: March 2021
AI Article Synopsis
Article Abstract
Plant pathogens have agricultural impacts on a global scale and resolving the timing and route of their spread can aid crop protection and inform control strategies. However, the evolutionary and phylogeographic history of plant pathogens in Eurasia remains largely unknown because of the difficulties in sampling across such a large landmass. Here, we show that turnip mosaic potyvirus (TuMV), a significant pathogen of brassica crops, spread from west to east across Eurasia from about the 17th century CE. We used a Bayesian phylogenetic approach to analyze 579 whole genome sequences and up to 713 partial sequences of TuMV, including 122 previously unknown genome sequences from isolates that we collected over the past five decades. Our phylogeographic and molecular clock analyses showed that TuMV isolates of the Asian-/ (BR) and basal-BR groups and world-3 (B3) subgroup spread from the center of emergence to the rest of Eurasia in relation to the host plants grown in each country. The migration pathways of TuMV have retraced some of the major historical trade arteries in Eurasia, a network that formed the Silk Road, and the regional variation of the virus is partly characterized by different type patterns of recombinants. Our study presents a complex and detailed picture of the timescale and major transmission routes of an important plant pathogen.
In spring 2022, 40 leaf samples of saffron plants harboring a wide variety of symptoms, including curling, yellowing, mosaic, dwarfing and leaf malformation were collected from three Khorasan provinces in Iran. These samples were processed using the virion-associated nucleic acid-based metagenomics approach (Moubset et al., 2022).
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Biotechnology in Plant Protection of MARA, Key Laboratory of Green Plant Protection of Zhejiang Province, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China.
The mechanisms by which plant viral proteases interact with host proteins and influence virus-host dynamics are not fully understood, particularly in potyviruses, the largest group of RNA viruses affecting plants.
Research shows that the protease NIa-Pro from the turnip mosaic virus (TuMV) is crucial for inducing hypersensitive cell death in the plant Nicotiana benthamiana by targeting and degrading the host protein DBP5.
Additionally, findings reveal that the TuMV-encoded nuclear inclusion b can mitigate NIa-Pro-induced cell death by interacting with DBP5, suggesting complex roles for viral proteases in disrupting host immunity.
Pathogenesis-related (PR) proteins are induced by abiotic and biotic stresses and generally considered as part of the plant defense mechanism. However, it remains yet largely unclear if and how they are involved in virus infection. Our recent quantitative, comparative proteomic study identified three PR-5 family proteins that are significantly differentially accumulated in the plasmodesmata (PD)-enriched fraction isolated from Nicotiana benthamiana leaves infected by turnip mosaic virus (TuMV).
Positive-sense RNA viruses remodel cellular cytoplasmic membranes as the membranous sources for the formation of viral replication organelles (VROs) for viral genome replication. In plants, they traffic through plasmodesmata (PD), plasma membrane-lined pores enabling cytoplasmic connections between cells for intercellular movement and systemic infection. In this study, we employed turnip mosaic virus (TuMV), a plant RNA virus to investigate the involvement of RTNLB3 and RTNLB6, two ER (endoplasmic reticulum) membrane-bending, PD-located reticulon-like (RTNL) non-metazoan group B proteins (RTNLBs) in viral infection.
