The manipulation of host plant defences by virulence effectors from plant pathogens
Plants, like animals, have a sophisticated immune system that is triggered by surface receptor-mediated recognition of pathogen-associated molecular patterns (PAMPs). Successful pathogens suppress these defence responses by the secretion of virulence determinants known as effectors. The eukaryotic oomycete pathogen Phytophthora infestans secretes and translocates effectors inside living host cells by means of a conserved motif (RXLR-EER) in the N-terminus of these proteins. In contrast, the bacterial pathogen Pectobacterium atrosepticum delivers effectors inside plant cells by means of a type III secretion system (T3SS). Selected T3SS or RXLR-EER-containing effectors will be screened using yeast-2-hybrid to identify host defence proteins that they target and manipulate to establish infection. Various biochemical, molecular and cell biological approaches will be used to visualise these protein-protein interactions as they occur during infection , and to investigate the roles that host target proteins play in plant defence.