Linnean Centre Seminar by Miguel Aranda

Summary:

Pepino mosaic virus (PepMV) (species Potexvirus pepini; family Alphaflexiviridae) is a globally important pathogen affecting tomato, a crop of major economic significance. PepMV is transmitted through seed and mechanical contact, facilitating both long- and short-distance dispersal. Since the emergence of PepMV epidemics in the Mediterranean basin, we have worked to develop a comprehensive set of strategies for disease control in tomato, including cross-protection and genetic screening approaches to identify sources of resistance. Cross-protection has been widely and successfully applied for disease management, making PepMV one of the most notable recent examples of this strategy. To identify resistance sources, we have employed both reverse and forward genetics approaches. Using reverse genetics, we identified several tomato proteins that interact with PepMV proteins. Following validation of these interactions, CRISPR/Cas9-mediated editing of the corresponding tomato genes revealed that several of them play proviral roles; knockout mutants displayed reduced susceptibility to PepMV. Using forward genetics, screening of an EMS-mutagenized tomato population led to the identification of a mutant line resistant to PepMV. Overall, several promising sources of resistance have been identified, and the underlying mechanisms are currently under investigation. Beyond its agronomic importance, PepMV also represents a tractable model for studying molecular interactions between viruses and plants.