description
- Plant diseases are a major constraint on food production. To rationally design efficient and resilient disease control strategies, it is essential to understand the molecular mechanisms underlying pathogen virulence. Most pathogens rely on secreted proteins called effectors to manipulate the host machinery for their benefit and perform their life cycle. In VAMEAP, we propose to characterize the virulence activities of the metalloprotease effector AVR-Pita from Magnaporthe oryzae, the causal agent of rice blast disease. Despite a strong selection pressure against this effector, AVR-Pita is maintained in populations of the pathogen suggesting a crucial role for the fitness of M. oryzae. Yet, next to nothing is known about the virulence activities or host targets of AVR-Pita. Here we propose an ambitious combination of biochemical and functional approaches to bridge this knowledge gap. We will survey the natural diversity and sequence polymorphisms in AVR-Pita and investigate the impact of its loss on the fitness of M. oryzae. We will identify the virulence targets of AVR-Pita using protein-protein interaction screens and characterize the protease activity of this effector. Beyond the knowledge that this project will gather on AVR-Pita, it will also help to understand the biology of metalloprotease effectors commonly found in fungal pathogens. The multidisciplinary approach developed in this project will be a powerful tool to further understand fungal virulence and help design new resistance strategies to control fungal crop diseases.