title: Elicitin-like proteins Oli-D1 and Oli-D2 from Pythium oligandrum trigger hypersensitive response in Nicotiana benthamiana and induce resistance against Botrytis cinerea in tomato.
abstract: The biocontrol agent Pythium oligandrum and its elicitin-like proteins oligandrins have been shown to induce disease resistance in a range of plants. In the present study, the ability of two oligandrins, Oli-D1 and Oli-D2, to induce an immune response and the possible molecular mechanism regulating the defence responses in Nicotiana benthamiana and tomato were investigated. Infiltration of recombinant Oli-D1 and Oli-D2 proteins induced a typical immune response in N. benthamiana including the induction of a hypersensitive response (HR), accumulation of reactive oxygen species and production of autofluorescence. Agrobacterium-mediated transient expression assays revealed that full-length Oli-D1 and Oli-D2 were required for full HR-inducing activity in N. benthamiana, and virus-induced gene silencing-mediated knockdown of some of the signalling regulatory genes demonstrated that NbSGT1 and NbNPR1 were required for Oli-D1 and Oli-D2 to induce HR in N. benthamiana. Subcellular localization analyses indicated that both Oli-D1 and Oli-D2 were targeted to the plasma membrane of N. benthamiana. When infiltrated or transiently expressed in leaves, Oli-D1 and Oli-D2 induced resistance against Botrytis cinerea in tomato and activated the expression of a set of genes involved in the jasmonic acid/ethylene (JA/ET)-mediated signalling pathway. Our results demonstrate that Oli-D1 and Oli-D2 are effective elicitors capable of inducing immune responses in plants, probably through the JA/ET-mediated signalling pathway, and that both Oli-D1 and Oli-D2 have potential for the development of bioactive formulae for crop disease control in practice.
authors.affiliation: National Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Ouyang
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Huang
authors.forename: Yongbo
authors.initials: Y
authors.lastname: Hong
authors.forename: Yafen
authors.initials: Y
authors.lastname: Zhang
authors.forename: Huijuan
authors.initials: H
authors.lastname: Zhang
authors.forename: Dayong
authors.initials: D
authors.lastname: Li
authors.forename: Fengming
authors.initials: F
authors.lastname: Song
mesh_terms: D020171:Botrytis / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism; D060467:Disease Resistance; D018506:Gene Expression Regulation, Plant; D018551:Solanum lycopersicum / Q000276:immunology / Q000382:microbiology*; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D011775:Pythium / Q000502:physiology*; D011994:Recombinant Proteins / Q000378:metabolism*; D014026:Nicotiana / Q000276:immunology / Q000382:microbiology*
chemical_list: D011994:Recombinant Proteins
keywords: Nicotiana benthamiana; Oli-D1/Oli-D2; defence response/resistance; hypersensitive response; oligandrin; tomato