BARLEY POWDERY MILDEW METALLO-PROTEASE-LIKE EFFECTOR: A UNIVERSAL VIRULENCE FACTOR IN FUNGI?
S. DAS GUPTA (1), M. Urban (2), G. Scalliet (3), K. Hammond-Kosack (2), L. Bindschedler (1) (1) Royal Holloway, University of London, United Kingdom; (2) Rothamstead Research, United Kingdom; (3) Syngenta, Switzerland; (4) Royal Holloway, University of London, United Kingdom

During barley infection with the obligate powdery mildew fungal pathogen, the Blumeria Effector Candidate 1019 (BEC1019) is a metallo-protease-like haustoria specific protein involved in the virulence of Blumeria graminis f. sp. hordei. BEC1019 host induced gene silencing (HIGS) led to reduced haustoria and hyphae formation and decreased spread of the disease. Moreover, introduction of BEC1019 in barley plants suppressed hypersensitive reaction (HR) triggered by bacterial pathogens. BEC1019 homologs are present in 96 out of 241 sequenced fungal genomes, including both human and plant pathogens. In particular, BEC1019 shares similarity with Candida albicans PRA1 virulence factor. These proteins are characterised by a HRXXH domain, closely related to the M35 family of zinc binding proteases. A conserved ETVIC domain mediates the suppression of HR in barley. Therefore these findings suggest a universal virulence function of BEC1019 homologs in fungi. Using gene knockout or HIGS approaches, this project aims to investigate the impact of BEC1019 homologs on the virulence of economically important wheat fungal pathogens. Impact on virulence will be investigated in BEC1019 knockouts mutants of Fusarium graminearum, the causative agent of Fusarium head blight (FHB). Alternatively, the BEC1019 homolog and other targets of B.graminis f.sp. tritici, (the causative agent of wheat powdery mildew) will be silenced with a novel HIGS protocol involving short antisense oligodeoxynucleotides (ODNs). This work will contribute to the understanding of the putative universal virulence role of this metallo-protease protein, with an ultimate goal of exploiting effector biology knowledge to devise new strategies for crop protection.

Abstract Number: P9-249
Session Type: Poster