title: Molecular evidence for the involvement of a polygalacturonase-inhibiting protein, GhPGIP1, in enhanced resistance to Verticillium and Fusarium wilts in cotton.
abstract: Polygalacturonase-inhibiting protein (PGIP), belonging to a group of plant defence proteins, specifically inhibits endopolygalacturonases secreted by pathogens. Herein, we showed that purified GhPGIP1 is a functional inhibitor of Verticillium dahliae and Fusarium oxysporum f. sp. vasinfectum, the two fungal pathogens causing cotton wilt. Transcription of GhPGIP1 was increased in cotton upon infection, wounding, and treatment with defence hormone and H2O2. Resistance by GhPGIP1 was examined by its virus-induced gene silencing in cotton and overexpression in Arabidopsis. GhPGIP1-silenced cotton was highly susceptible to the infections. GhPGIP1 overexpression in transgenic Arabidopsis conferred resistance to the infection, accompanied by enhanced expression of pathogenesis-related proteins (PRs), isochorismate synthase 1 (ICS1), enhanced disease susceptibility 1 (EDS1), and phytoalexin-deficient 4 (PAD4) genes. Transmission electron microscopy revealed cell wall alteration and cell disintegration in plants inoculated with polygalacturonase (PGs), implying its role in damaging the cell wall. Docking studies showed that GhPGIP1 interacted strongly with C-terminal of V. dahliae PG1 (VdPG1) beyond the active site but weakly interacted with C-terminal of F. oxysporum f. sp. vasinfectum (FovPG1). These findings will contribute towards the understanding of the roles of PGIPs and in screening potential combat proteins with novel recognition specificities against evolving pathogenic factors for countering pathogen invasion.
authors.affiliation: College of Science, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China.
authors.forename: Nana
authors.initials: N
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Cotton Biology, Institute of Cotton Research of the Chinese Academy of Agricultural Sciences, Anyang 455000, People's Republic of China.
authors.forename: Xueyan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Science, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Science, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: College of Science, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China.
authors.forename: Xiancai
authors.initials: X
authors.lastname: Li
authors.affiliation: College of Science, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China.
authors.forename: Yakun
authors.initials: Y
authors.lastname: Pei
authors.affiliation: State Key Laboratory of Cotton Biology, Institute of Cotton Research of the Chinese Academy of Agricultural Sciences, Anyang 455000, People's Republic of China.
authors.forename: Fuguang
authors.initials: F
authors.lastname: Li
authors.affiliation: College of Science, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China.
authors.forename: Yuxia
authors.initials: Y
authors.lastname: Hou
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D060585:Fusariosis / Q000276:immunology*; D005670:Fusarium / Q000276:immunology*; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D003368:Gossypium / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000378:metabolism; D019751:Intramolecular Transferases / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology*; D057865:Plant Immunity; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D020172:Verticillium / Q000276:immunology*; D014867:Water / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; C118837:EDS1 protein, Arabidopsis; C081479:PGIP protein, plant; D010940:Plant Proteins; D014867:Water; D006861:Hydrogen Peroxide; D002265:Carboxylic Ester Hydrolases; C400766:PAD4 protein, Arabidopsis; D019751:Intramolecular Transferases; C058486:isochorismate synthase