title: BcGs1, a glycoprotein from Botrytis cinerea, elicits defence response and improves disease resistance in host plants.
abstract: In this study, a necrosis-inducing protein was purified from the culture filtrate of the necrotrophic fungus Botrytis cinerea BC-98 strain. Secreted proteins were collected and fractionated by liquid chromatography. The fraction with the highest necrosis-inducing activity was further purified. A glycoprotein named BcGs1 was identified by 2D electrophoresis and mass spectrometry. The BcGs1 protein consisted of 672 amino acids with a theoretical molecular weight of 70.487 kDa. Functional domain analysis indicated that BcGs1 was a glucan 1,4-alpha-glucosidase, a cell wall-degrading enzyme, with a Glyco_hydro_15 domain and a CBM20_glucoamylase domain. The BcGs1 protein caused necrotic lesions that mimicked a typical hypersensitive response and H2O2 production in tomato and tobacco leaves. BcGs1-treated plants exhibited resistance to B. cinerea, Pseudomonas syringae pv. tomato DC3000 and tobacco mosaic virus in systemic leaves. In addition, BcGs1 triggered elevation of the transcript levels of the defence-related genes PR-1a, TPK1b and Prosystemin. This is the first report of a Botrytis glucan 1,4-alpha-glucosidase triggering host plant immunity as an elicitor. These results lay a foundation for further study of the comprehensive interaction between plants and necrotrophic fungi.
authors.affiliation: The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhong-guan-cun South Street, Beijing 100081, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhong-guan-cun South Street, Beijing 100081, China.
authors.forename: Yunhua
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhong-guan-cun South Street, Beijing 100081, China.
authors.forename: Dewen
authors.initials: D
authors.lastname: Qiu
authors.affiliation: The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhong-guan-cun South Street, Beijing 100081, China.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zeng
authors.affiliation: The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhong-guan-cun South Street, Beijing 100081, China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Guo
authors.affiliation: The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhong-guan-cun South Street, Beijing 100081, China. Electronic address: yangxiufen@caas.cn.
authors.forename: Xiufen
authors.initials: X
authors.lastname: Yang
mesh_terms: D020171:Botrytis / Q000737:chemistry / Q000502:physiology*; D005656:Fungal Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005087:Glucan 1,4-alpha-Glucosidase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D018551:Solanum lycopersicum / Q000235:genetics / Q000382:microbiology*; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology*; D018515:Plant Leaves / Q000235:genetics / Q000382:microbiology; D014026:Nicotiana / Q000235:genetics / Q000382:microbiology*
chemical_list: D005656:Fungal Proteins; D006023:Glycoproteins; D005087:Glucan 1,4-alpha-Glucosidase
keywords: Defence response; Disease resistance; Necrosis-inducing activity; Necrotrophic fungi; Systemic acquired resistance