title: A novel protein elicitor (SsCut) from Sclerotinia sclerotiorum induces multiple defense responses in plants.
abstract: In this study, we report the cloning of the SsCut gene encoding cutinase from Sclerotinia sclerotiorum. We isolated a 609-bp cDNA encoding a polypeptide of 202 amino acids with a molecular weight of 20.4 kDa. Heterologous expression of SsCut in Escherichia coli (His-SsCut) caused the formation of lesions in tobacco that closely resembled hypersensitive response lesions. Mutational analysis identified the C-terminal-half peptide and the same amino acids indispensable for both enzyme and elicitor activity. His-SsCut was caused cell death in Arabidopsis, soybean (Glycine max), oilseed rape (Brassica napus), rice (Oryza sativa), maize (Zea mays), and wheat (Triticum aestivum), indicating that both dicot and monocot species are responsive to the elicitor. Furthermore, the elicitation of tobacco was effective in the induction of the activities of hydrogen peroxide, phenylalanine ammonia-lyase, peroxides, and polyphenol oxidase. His-SsCut-treated plants exhibited enhanced resistance as indicated by a significant reduction in the number and size of S. sclerotiorum, Phytophthora sojae, and P. nicotianae lesions on leaves relative to controls. Real-time PCR results indicated that the expression of defense-related genes and genes involved in signal transduction were induced by His-SsCut. Our results demonstrate that SsCut is an elicitor that triggers defense responses in plants and will help to clarify its relationship to downstream signaling pathways that induce defense responses.
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Anhui Agricultural University, Hefei, 230036, China, hjzhang@ahau.edu.cn.
authors.forename: Huajian
authors.initials: H
authors.lastname: Zhang
authors.forename: Qun
authors.initials: Q
authors.lastname: Wu
authors.forename: Shun
authors.initials: S
authors.lastname: Cao
authors.forename: Tongyao
authors.initials: T
authors.lastname: Zhao
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.forename: Peitong
authors.initials: P
authors.lastname: Zhuang
authors.forename: Xiuhong
authors.initials: X
authors.lastname: Zhou
authors.forename: Zhimou
authors.initials: Z
authors.lastname: Gao
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D002265:Carboxylic Ester Hydrolases / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D004156:Catechol Oxidase / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions; D008969:Molecular Sequence Data; D010650:Phenylalanine Ammonia-Lyase / Q000378:metabolism; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D010944:Plants / Q000235:genetics* / Q000382:microbiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013997:Time Factors; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D004156:Catechol Oxidase; D002265:Carboxylic Ester Hydrolases; C019952:cutinase; D010650:Phenylalanine Ammonia-Lyase