title: FgMon1, a guanine nucleotide exchange factor of FgRab7, is important for vacuole fusion, autophagy and plant infection in Fusarium graminearum.
abstract: The Ccz1-Mon1 protein complex, the guanine nucleotide exchange factor (GEF) of the late endosomal Rab7 homolog Ypt7, is required for the late step of multiple vacuole delivery pathways, such as cytoplasm-to-vacuole targeting (Cvt) pathway and autophagy processes. Here, we identified and characterized the yeast Mon1 homolog in Fusarium graminearum, named FgMon1. FgMON1 encodes a trafficking protein and is well conserved in filamentous fungi. Targeted gene deletion showed that the ∆Fgmon1 mutant was defective in vegetative growth, asexual/sexual development, conidial germination and morphology, plant infection and deoxynivalenol production. Cytological examination revealed that the ∆Fgmon1 mutant was also defective in vacuole fusion and autophagy, and delayed in endocytosis. Yeast two hybrid and in vitro GST-pull down assays approved that FgMon1 physically interacts with a Rab GTPase FgRab7 which is also important for the development, infection, membrane fusion and autophagy in F. graminearum. FgMon1 likely acts as a GEF of FgRab7 and constitutively activated FgRab7 was able to rescue the defects of the ∆Fgmon1 mutant. In summary, our study provides evidences that FgMon1 and FgRab7 are critical components that modulate vesicle trafficking, endocytosis and autophagy, and thereby affect the development, plant infection and DON production of F. graminearum.
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Li
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Luping
authors.initials: L
authors.lastname: Liu
authors.affiliation: Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
authors.forename: Huaigu
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Zhengguang
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D001343:Autophagy / Q000235:genetics / Q000502:physiology*; D001692:Biological Transport / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005670:Fusarium / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D020662:Guanine Nucleotide Exchange Factors / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D008561:Membrane Fusion; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D009154:Mutation; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology; D011485:Protein Binding; D013172:Spores, Fungal / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D014908:Triticum / Q000382:microbiology; D014617:Vacuoles / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D000090802:rab7 GTP-Binding Proteins
chemical_list: D005656:Fungal Proteins; D020662:Guanine Nucleotide Exchange Factors; D000090802:rab7 GTP-Binding Proteins; D020691:rab GTP-Binding Proteins