title: MoVam7, a conserved SNARE involved in vacuole assembly, is required for growth, endocytosis, ROS accumulation, and pathogenesis of Magnaporthe oryzae.
abstract: Soluble NSF attachment protein receptor (SNARE) proteins play a central role in membrane fusion and vesicle transport of eukaryotic organisms including fungi. We previously identified MoSce22 as a homolog of Saccharomyces cerevisiae SNARE protein Sec22 to be involved in growth, stress resistance, and pathogenicity of Magnaporthe oryzae. Here, we provide evidences that MoVam7, an ortholog of S. cerevisiae SNARE protein Vam7, exerts conserved functions in vacuolar morphogenesis and functions in pathogenicity of M. oryzae. Staining with neutral red and FM4-64 revealed the presence of abnormal fragmented vacuoles and an absence of the Spitzenkörper body in the ΔMovam7 mutant. The ΔMovam7 mutant also exhibited reduced vegetative growth, poor conidiation, and failure to produce the infection structure appressorium. Additionally, treatments with cell wall perturbing agents indicated weakened cell walls and altered distributions of the cell wall component chitin. Furthermore, the ΔMovam7 mutant showed a reduced accumulation of reactive oxygen species (ROS) in the hyphal apex and failed to cause diseases on the rice plant. In summary, our studies indicate that MoVam7, like MoSec22, is a component of the SNARE complex whose functions in vacuole assembly also underlies the growth, conidiation, appressorium formation, and pathogenicity of M. oryzae. Further studies of MoVam7, MoSec22, and additional members of the SNARE complex are likely to reveal critical mechanisms in vacuole formation and membrane trafficking that is linked to fungal pathogenicity.
authors.affiliation: Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, and Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China.
authors.forename: Xianying
authors.initials: X
authors.lastname: Dou
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.forename: Zhongqiang
authors.initials: Z
authors.lastname: Qi
authors.forename: Wenwen
authors.initials: W
authors.lastname: Song
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Guo
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.forename: Zhengguang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zheng
mesh_terms: D004705:Endocytosis; D005656:Fungal Proteins / Q000502:physiology*; D020082:Magnaporthe / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D050600:SNARE Proteins / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins; D050825:Synaptosomal-Associated Protein 25; D014617:Vacuoles / Q000378:metabolism; D014774:Virulence
chemical_list: D005656:Fungal Proteins; D017382:Reactive Oxygen Species; D050600:SNARE Proteins; D029701:Saccharomyces cerevisiae Proteins; D050825:Synaptosomal-Associated Protein 25; C494205:VAM7 protein, S cerevisiae