Non-TAL Effectors From Xanthomonas oryzae pv. oryzae Suppress Peptidoglycan-Triggered MAPK Activation in Rice

Frontiers in Plant Science

Junhui Zhou¹  Juying Long¹  Congfeng Song¹  Bing Yang³  Fang Yan⁴  Huanbin Zhou⁴ 

[1] Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States;Division of Plant Sciences, University of Missouri, Columbia, MO, United States;Donald Danforth Plant Science Center, St. Louis, MO, United States;Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China;Key Laboratory of Monitoring and Management of Plant Diseases and Insects, Ministry of Education, Nanjing Agricultural University, Nanjing, China;

关键词: Xanthomonas;    type III effector;    TAL effector;    non-TAL effector;    MAPK;    immunity;   

DOI  :  10.3389/fpls.2018.01857

来源: DOAJ

【 摘 要 】

Xanthomonas oryzae pv. oryzae, the causal pathogen of bacterial blight of rice, depends on its type III secretion system and associated effector proteins to grow and colonize the vascular tissues of rice plants. The type III effectors include a family of closely related transcription activator-like (TAL) effectors and the rest of diverse effectors, so-called non-TAL effectors. Our understanding of non-TAL effectors for pathogenesis in rice blight is still limited. Here we report a feasible method to rapidly detect the activation of mitogen-activated protein kinase pathway in rice mesophyll protoplasts by the X. oryzae pv. oryzae derived peptidoglycan and screen for virulent effectors that can suppress the pathogen-associated molecular pattern triggered immunity (PTI) response. Amongst 17 non-TAL effectors transiently expressed in rice cells, we found that three effectors (XopZ, XopN, and XopV) were able to suppress the peptidoglycan-triggered MAPK activation. The triple mutant of the X. oryzae pv. oryzae strain PXO99A lacking XopZ, XopN, and XopV showed additively reduced virulence. Adding back either of genes restored the virulence of the triple mutant. Our results demonstrate the collective and redundant ability of defense suppression by non-TAL effectors in causing bacterial blight of rice.

【 授权许可】

Unknown