Recognition of the Hyaloperonospora parasitica effector ATR13 triggers resistance against oomycete, bacterial, and viral pathogens

• Published in: Proceedings of the National Academy of Sciences - PNAS 2008-01, Vol.105 (3), p.1091-1096
• Main Authors: Rentel, Maike C, Leonelli, Lauriebeth, Dahlbeck, Douglas, Zhao, Bingyu, Staskawicz, Brian J
• Format: Article
• Language: English
• Subjects: Algal Proteins - genetics; Algal Proteins - metabolism; Alleles; Apoptosis; Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Bacteria; Biological Sciences; Cell death; Crops; Disease resistance; effector genes; Epitopes; Flowers & plants; fungal diseases of plants; fungal proteins; Gene Expression; gene transfer; Genes; genetically engineered microorganisms; host-pathogen relationships; Leaves; Lycopersicon esculentum; Mosaic Viruses - genetics; Mosaic Viruses - pathogenicity; Mosaic Viruses - physiology; Nicotiana - cytology; Nicotiana - genetics; Nicotiana - growth & development; Nicotiana - metabolism; Nicotiana benthamiana; Oomycetes; Oomycetes - genetics; Oomycetes - pathogenicity; Oomycetes - physiology; Pathogens; Peronospora parasitica; Phytophthora; Plant cells; Plant Diseases - genetics; Plant Diseases - immunology; Plant Diseases - microbiology; Plant Diseases - virology; Plant pathology; Plants; Plasmids; Proteins; Pseudomonas syringae; Pseudomonas syringae - genetics; Pseudomonas syringae - physiology; Pseudomonas syringae pv. tomato; resistance mechanisms; Solanum tuberosum; Turnip mosaic virus; Viruses
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0711215105

Phytopathogenic oomycetes cause some of the most devastating diseases affecting agricultural crops. Hyaloperonospora parasitica is a native oomycete pathogen of Arabidopsis and is related to other oomycete phytopathogens that include several species of Phytophthora, including the causal agent of potato late blight. Recently, four oomycete effector genes have been isolated, and several oomycete genomes have been sequenced. We have developed an efficient and genetically amenable system to test putative effector genes using the bacterial pathogen Pseudomonas syringae pv. tomato DC3000. The H. parasitica effector protein ATR13 was delivered via P. syringae by fusing the ATR13 gene with the avrRpm1 type three secretion signal peptide, a bacterial sequence that allows transfer of proteins into the host cell through the bacterial type III secretion system. We also inserted ATR13 into the genome of the turnip mosaic virus, a single-stranded RNA virus. Our results show that delivery of ATR13 via the bacterial or viral pathogen triggers defense responses in plants containing the cognate resistance protein RPP13Nd, which restricts proliferation of both pathogens. Hence, recognition of ATR13 by RPP13 initiates defense responses that are effective against oomycete, bacterial and viral pathogens, pointing to a common defense mechanism. We have characterized regions of the RPP13Nd resistance protein that are essential for effector recognition and/or downstream signaling, using transient coexpression in Nicotiana benthamiana.