title: Magnaporthe oryzae effectors MoHEG13 and MoHEG16 interfere with host infection and MoHEG13 counteracts cell death caused by Magnaporthe-NLPs in tobacco.
abstract: Adapted pathogens are able to modulate cell responses of their hosts most likely due to the activity of secreted effector molecules thereby enabling colonisation by ostensible nonhost pathogens. It is postulated that host and nonhost pathogens of a given plant species differ in their repertoire of secreted effector molecules that are able to suppress plant resistance. We pursued the strategy of identifying novel effectors of Magnaporthe oryzae, the causal agent of blast disease, by comparing the infection process of closely related host vs. nonhost Magnaporthe species on barley (Hordeum vulgare L.). When both types of pathogen simultaneously attacked the same cell, the nonhost isolate became a successful pathogen possibly due to potent effectors secreted by the host isolate. Microarray studies led to a set of M. oryzae Hypothetical Effector Genes (MoHEGs) which were classified as Early- and LateMoHEGs according to the maximal transcript abundance during colonization of barley. Interestingly, orthologs of these MoHEGs from a nonhost pathogen were similarly regulated when investigated in a host situation, suggesting evolutionary conserved functions. Knockout mutants of MoHEG16 from the group of EarlyMoHEGs were less virulent on barley and microscopic studies revealed an attenuated transition from epidermal to mesophyll colonization. MoHEG13, a LateMoHEG, was shown to antagonize cell death induced by M. oryzae Necrosis-and ethylene-inducing-protein-1 (Nep1)-like proteins in Nicotiana benthamiana. MoHEG13 has a virulence function as a knockout mutant showed attenuated disease progression when inoculated on barley.
authors.affiliation: Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany.
authors.forename: Valerie
authors.initials: V
authors.lastname: Mogga
authors.affiliation: Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany.
authors.forename: Rhoda
authors.initials: R
authors.lastname: Delventhal
authors.affiliation: Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany.
authors.forename: Denise
authors.initials: D
authors.lastname: Weidenbach
authors.affiliation: Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany.
authors.forename: Samantha
authors.initials: S
authors.lastname: Langer
authors.affiliation: Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany.
authors.forename: Philipp M
authors.initials: PM
authors.lastname: Bertram
authors.affiliation: Institute of Biotechnology and Drug Research, Erwin-Schrödinger-Strasse 56, 67663, Kaiserslautern, Germany.
authors.forename: Karsten
authors.initials: K
authors.lastname: Andresen
authors.affiliation: Institute of Biotechnology and Drug Research, Erwin-Schrödinger-Strasse 56, 67663, Kaiserslautern, Germany.|Biotechnology, Johannes Gutenberg-University, 55099, Mainz, Germany.
authors.forename: Eckhard
authors.initials: E
authors.lastname: Thines
authors.affiliation: INRA, UMR BGPI, Campus International de Baillarguet, TA A-54/K, 34398, Montpellier Cedex 5, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kroj
authors.affiliation: Department of Plant Physiology, RWTH Aachen University, 52056, Aachen, Germany. schaffrath@bio3.rwth-aachen.de.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schaffrath
mesh_terms: D000595:Amino Acid Sequence; D016923:Cell Death; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D055786:Gene Knockout Techniques; D017930:Genes, Reporter; D001467:Hordeum / Q000166:cytology / Q000382:microbiology* / Q000502:physiology; D058507:Host Specificity; D054884:Host-Pathogen Interactions; D020082:Magnaporthe / Q000472:pathogenicity / Q000502:physiology*; D058503:Mesophyll Cells / Q000382:microbiology / Q000502:physiology; D009154:Mutation; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000166:cytology / Q000382:microbiology / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D012697:Serine Endopeptidases; D014026:Nicotiana / Q000166:cytology / Q000382:microbiology* / Q000502:physiology; D014774:Virulence
chemical_list: D005656:Fungal Proteins; D012333:RNA, Messenger; C117340:NGF-like protease; D012697:Serine Endopeptidases
keywords: Barley; Effector proteins; Magnaporthe oryzae; Necrosis