title: PeaT1-induced systemic acquired resistance in tobacco follows salicylic acid-dependent pathway.
abstract: Systemic acquired resistance (SAR) is an inducible defense mechanism which plays a central role in protecting plants from pathogen attack. A new elicitor, PeaT1 from Alternaria tenuissima, was expressed in Escherichia coil and characterized with systemic acquired resistance to tobacco mosaic virus (TMV). PeaT1-treated plants exhibited enhanced systemic resistance with a significant reduction in number and size of TMV lesions on wild tobacco leaves as compared with control. The quantitative analysis of TMV CP gene expression with real-time quantitative PCR showed there was reduction in TMV virus concentration after PeaT1 treatment. Similarly, peroxidase (POD) activity and lignin increased significantly after PeaT1 treatment. The real-time quantitative PCR revealed that PeaT1 also induced the systemic accumulation of pathogenesis-related gene, PR-1a and PR-1b which are the markers of systemic acquired resistance (SAR), NPR1 gene for salicylic acid (SA) signal transduction pathway and PAL gene for SA synthesis. The accumulation of SA and the failure in development of similar level of resistance as in wild type tobacco plants in PeaT1 treated nahG transgenic tobacco plants indicated that PeaT1-induced resistance depended on SA accumulation. The present work suggested that the molecular mechanism of PeaT1 inducing disease resistance in tobacco was likely through the systemic acquired resistance pathway mediated by salicylic acid and the NPR1 gene.
authors.affiliation: Key Laboratory for Biological Control of Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Xiufen
authors.initials: X
authors.lastname: Yang
authors.forename: Dewen
authors.initials: D
authors.lastname: Qiu
authors.forename: Lihua
authors.initials: L
authors.lastname: Guo
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zeng
authors.forename: Jianjun
authors.initials: J
authors.lastname: Mao
authors.forename: Qiufeng
authors.initials: Q
authors.lastname: Gao
mesh_terms: D000528:Alternaria / Q000737:chemistry*; D017931:DNA Primers / Q000235:genetics; D004926:Escherichia coli; D005656:Fungal Proteins / Q000378:metabolism*; D007113:Immunity, Innate / Q000276:immunology*; D008031:Lignin / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D010935:Plant Diseases / Q000821:virology*; D018515:Plant Leaves / Q000378:metabolism; D016133:Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*; D014026:Nicotiana / Q000276:immunology* / Q000821:virology; D014027:Tobacco Mosaic Virus / Q000276:immunology*; D014170:Transformation, Genetic; D014764:Viral Proteins / Q000378:metabolism
chemical_list: D017931:DNA Primers; D005656:Fungal Proteins; D014764:Viral Proteins; D008031:Lignin; D009195:Peroxidase