title: The Pseudomonas syringae type III effector HopF2 suppresses Arabidopsis stomatal immunity.
abstract: Pseudomonas syringae subverts plant immune signalling through injection of type III secreted effectors (T3SE) into host cells. The T3SE HopF2 can disable Arabidopsis immunity through Its ADP-ribosyltransferase activity. Proteomic analysis of HopF2 interacting proteins identified a protein complex containing ATPases required for regulating stomatal aperture, suggesting HopF2 may manipulate stomatal immunity. Here we report HopF2 can inhibit stomatal immunity independent of its ADP-ribosyltransferase activity. Transgenic expression of HopF2 in Arabidopsis inhibits stomatal closing in response to P. syringae and increases the virulence of surface inoculated P. syringae. Further, transgenic expression of HopF2 inhibits flg22 induced reactive oxygen species production. Intriguingly, ADP-ribosyltransferase activity is dispensable for inhibiting stomatal immunity and flg22 induced reactive oxygen species. Together, this implies HopF2 may be a bifunctional T3SE with ADP-ribosyltransferase activity required for inhibiting apoplastic immunity and an independent function required to inhibit stomatal immunity.
authors.affiliation: Department of Cell & Systems Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada.
authors.forename: Brenden
authors.initials: B
authors.lastname: Hurley
authors.affiliation: Department of Plant Pathology, University of California Davis, Davis, CA, United States of America.
authors.forename: Donghyuk
authors.initials: D
authors.lastname: Lee
authors.affiliation: Department of Cell & Systems Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada.
authors.forename: Adam
authors.initials: A
authors.lastname: Mott
authors.affiliation: Department of Cell & Systems Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Wilton
authors.affiliation: Department of Plant Pathology, University of California Davis, Davis, CA, United States of America.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Leslie Dan Faculty of Pharmacy, Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Yulu C
authors.initials: YC
authors.lastname: Liu
authors.affiliation: Leslie Dan Faculty of Pharmacy, Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Stephane
authors.initials: S
authors.lastname: Angers
authors.affiliation: Department of Plant Pathology, University of California Davis, Davis, CA, United States of America.
authors.forename: Gitta
authors.initials: G
authors.lastname: Coaker
authors.affiliation: Department of Cell & Systems Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada; Centre for the Analysis of Genome Evolution & Function, University of Toronto, Toronto, Ontario, Canada.
authors.forename: David S
authors.initials: DS
authors.lastname: Guttman
authors.affiliation: Department of Cell & Systems Biology, University of Toronto, 25 Willcocks St., Toronto, Ontario, Canada; Centre for the Analysis of Genome Evolution & Function, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Darrell
authors.initials: D
authors.lastname: Desveaux
mesh_terms: D036002:ADP Ribose Transferases / Q000235:genetics* / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics* / Q000276:immunology; D001426:Bacterial Proteins / Q000235:genetics*; D054884:Host-Pathogen Interactions / Q000235:genetics* / Q000276:immunology; D057865:Plant Immunity / Q000235:genetics*; D054046:Plant Stomata / Q000235:genetics / Q000276:immunology*; D030821:Plants, Genetically Modified; D040901:Proteomics; D044224:Pseudomonas syringae / Q000378:metabolism / Q000472:pathogenicity; D000069296:Type III Secretion Systems / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D000069296:Type III Secretion Systems; D036002:ADP Ribose Transferases