Understanding and Preventing Plant Susceptibility to Aphids

Aphids are devastating insect pests of crops globally, and pose a major threat to food security. Crucially, there is a lack of durable genetic crop resistance against aphids, and current control relies almost exclusively on insecticides, which are costly and damaging to the environment and to which aphids develop resistance. These insects deliver proteins inside host plants, called effectors, to suppress the plant immune system and enhance susceptibility. I recently discovered that these effectors exhibit their activity via interacting with host plant proteins pointing to important conceptual parallels between plant-insect and plant-microbe interactions. This raises important new questions that urgently need to be addressed to enable development of novel protection strategies against aphids that are durable and sustainable. These are:What is the mechanistic and structural basis of aphid effector-triggered susceptibility?How can we interfere with aphid effector-triggered susceptibility?APHIDTRAP will address these questions using an innovative strategy: 1) I will introduce a structural biology approach to the insect effector biology field to reveal protein 3D structures of aphid effectors and their host protein targets in bound and unbound state, and determine how mutations in these proteins affect interactions and protein functions. 2) I will use both natural variants and mutants of effectors and host protein targets, combined with in planta functional assays to explore plant-aphid molecular co-evolution. 3) I will identify host protein target interactomes and investigate how mutations affect network functionality. 4) I will use information generated in 1-3 to develop and apply a synthetic biology approach to prevent aphid effector-triggered susceptibility in potato crop plants. APHIDTRAP’s vision is to elucidate the mechanisms that underlie susceptibility to aphids and investigate how we can interfere with these to reduce crop susceptibility to insect pests.