title: Pseudomonas syringae effector AvrPto blocks innate immunity by targeting receptor kinases.
abstract: Plants use receptor kinases, such as FLS2 and EFR, to perceive bacterial pathogens and initiate innate immunity. This immunity is often suppressed by bacterial effectors, allowing pathogen propagation. To counteract, plants have evolved disease resistance genes that detect the bacterial effectors and reinstate resistance. The Pseudomonas syringae effector AvrPto promotes infection in susceptible plants but triggers resistance in plants carrying the protein kinase Pto and the associated resistance protein Prf. Here we show that AvrPto binds receptor kinases, including Arabidopsis FLS2 and EFR and tomato LeFLS2, to block plant immune responses in the plant cell. The ability to target receptor kinases is required for the virulence function of AvrPto in plants. The FLS2-AvrPto interaction and Pto-AvrPto interaction appear to share similar sequence requirements, and Pto competes with FLS2 for AvrPto binding. The results suggest that the mechanism by which AvrPto recognizes virulence targets is linked to the evolution of Pto, which, in association with Prf, recognizes the bacterium and triggers strong resistance.
authors.affiliation: State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100094, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Xiang
authors.forename: Na
authors.initials: N
authors.lastname: Zong
authors.forename: Yan
authors.initials: Y
authors.lastname: Zou
authors.forename: Yong
authors.initials: Y
authors.lastname: Wu
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Weiman
authors.initials: W
authors.lastname: Xing
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Tang
authors.forename: Lihuang
authors.initials: L
authors.lastname: Zhu
authors.forename: Jijie
authors.initials: J
authors.lastname: Chai
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Zhou
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000382:microbiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism / Q000502:physiology*; D007113:Immunity, Innate / Q000235:genetics; D018551:Solanum lycopersicum / Q000201:enzymology / Q000382:microbiology*; D020935:MAP Kinase Signaling System; D010940:Plant Proteins / Q000378:metabolism*; D025941:Protein Interaction Mapping; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D044224:Pseudomonas syringae / Q000276:immunology / Q000472:pathogenicity*; D037521:Virulence Factors / Q000378:metabolism / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D010940:Plant Proteins; C120613:Prf protein, Lycopersicon esculentum; D037521:Virulence Factors; C081695:avrPto protein, Pseudomonas syringae; D011494:Protein Kinases; C411853:FLS2 protein, Arabidopsis; C084354:Pto protein, Lycopersicon; D017346:Protein Serine-Threonine Kinases