Project partners

Jane Parker, Max Planck Institute for Plant Breeding Research, Germany
Guido van den Ackerveken, Utrecht University, The Netherlands
Jonathan D.G. Jones, John Innes Centre, UK

Plants have evolved multiple layers of defence to prevent the invasion of micro-organisms but the processes underlying them are still poorly understood. To overcome such defence systems pathogens have evolved a battery of proteins (effectors) that suppress host resistance at several levels. A new class of pathogen effector proteins has recently been identified in the oomycetes, a taxonomic group of pathogens causing serious yield losses in many crops. Recent work on oomycete effectors has revealed conserved motifs, proposed to be target effectors into the host cell, which enable their identification through bioinformatics. In this proposal we will deploy the effector complement of the obligate biotrophic oomycete Hyaloperonospora parsitica (Hpat) that causes downy mildew disease of Arabidopsis. Four major EU labs with complementary expertise on the Arabidopsis-Hpat system will identify effectors from the recently released Hpat genome sequence, study their variation in 5 races of Hpat, and use them to understand their role in host plant resistance and susceptibility. We will adopt a range of delivery systems and assays to reveal the roles of different effectors in triggering or suppressing host defence mechanisms, exploiting natural variation in host and pathogen, and identify the host proteins with which they interact. Thus, we aim to use the Hpat genome to probe the Arabidopsis genome for defence and susceptibility determinants. Knowledge obtained will be important in understanding fundamental processes of plant disease resistance and should generate novel approaches to producing disease resistant crops.