Link to home

Identification and Characterization of In planta–Expressed Secreted Effector Proteins from Magnaporthe oryzae That Induce Cell Death in Rice

February 2013 , Volume 26 , Number  2
Pages  191 - 202

Songbiao Chen,1,2,3 Pattavipha Songkumarn,2 R. C. Venu,2 Malali Gowda,2 Maria Bellizzi,2 Jinnan Hu,2 Wende Liu,1 Daniel Ebbole,4 Blake Meyers,5 Thomas Mitchell,2 and Guo-Liang Wang1,2

1State Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; 2Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, U.S.A.; 3Biotechnology Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian 350003, China; 4Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 79016, U.S.A.; 5Delaware Biotechnology Institute, University of Delaware, Newark, DE, U.S.A.

Go to article:
Accepted 24 September 2012.

Interactions between rice and Magnaporthe oryzae involve the recognition of cellular components and the exchange of complex molecular signals from both partners. How these interactions occur in rice cells is still elusive. We employed robust-long serial analysis of gene expression, massively parallel signature sequencing, and sequencing by synthesis to examine transcriptome profiles of infected rice leaves. A total of 6,413 in planta–expressed fungal genes, including 851 genes encoding predicted effector proteins, were identified. We used a protoplast transient expression system to assess 42 of the predicted effector proteins for the ability to induce plant cell death. Ectopic expression assays identified five novel effectors that induced host cell death only when they contained the signal peptide for secretion to the extracellular space. Four of them induced cell death in Nicotiana benthamiana. Although the five effectors are highly diverse in their sequences, the physiological basis of cell death induced by each was similar. This study demonstrates that our integrative genomic approach is effective for the identification of in planta–expressed cell death–inducing effectors from M. oryzae that may play an important role facilitating colonization and fungal growth during infection.

© 2013 The American Phytopathological Society