title: Genome-wide functional characterization of putative peroxidases in the head blight fungus Fusarium graminearum.
abstract: Reactive oxygen species (ROS) are associated with various developmental processes and host-pathogen interactions in pathogenic fungi. Peroxidases are a group of ROS-detoxifying enzymes that are involved in the oxidative stress response and in a variety of physiological processes. In this study, we performed a genome-wide functional characterization of putative peroxidase genes in Fusarium graminearum, a head blight pathogen of cereal crops. We identified 31 putative peroxidase genes and generated deletion mutants for these genes. Twenty-six of the deletion mutants showed developmental phenotypes indistinguishable from that of the wild-type, and five deletion mutants exhibited phenotypic changes in at least one phenotypic category. Four deletion mutants, fca6, fca7, fpx1 and fpx15, showed increased sensitivity to extracellular H2O2. Deletion mutants of FCA7 also exhibited reduced virulence and increased trichothecene production compared with those of the wild-type strain, suggesting that Fca7 may play an important role in the host-pathogen interaction in F. graminearum. To identify the transcription factors (TFs) regulating FCA6, FCA7, FPX1 and FPX15 in response to oxidative stress, we screened an F. graminearum TF mutant library for growth in the presence of H2O2and found that multiple TFs co-regulated the expression of FCA7 under oxidative stress conditions. These results demonstrate that a complex network of transcriptional regulators of antioxidant genes is involved in oxidative stress responses in this fungus. Moreover, our study provides insights into the roles of peroxidases in developmental processes and host-pathogen interactions in plant-pathogenic fungi.
authors.affiliation: Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea.
authors.forename: Yoonji
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Center for Food and Bioconvergence, Seoul National University, Seoul, 08826, South Korea.
authors.forename: Hokyoung
authors.initials: H
authors.lastname: Son
authors.affiliation: Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Shin
authors.affiliation: Eco-friendly New Materials Research Group, Research Center for Biobased Chemistry, Division of Convergence Chemistry, Korea Research Institute of Chemical Technology, Daejeon, 34114, South Korea.
authors.forename: Gyung Ja
authors.initials: GJ
authors.lastname: Choi
authors.affiliation: Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea.
authors.forename: Yin-Won
authors.identifier: 0000-0002-9652-4102
authors.initials: YW
authors.lastname: Lee
mesh_terms: D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005670:Fusarium / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D015966:Gene Expression Regulation, Fungal / Q000235:genetics / Q000502:physiology; D018384:Oxidative Stress / Q000235:genetics / Q000502:physiology; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D013172:Spores, Fungal / Q000201:enzymology / Q000235:genetics / Q000472:pathogenicity
chemical_list: D005656:Fungal Proteins; D010544:Peroxidases
keywords: Fusarium graminearum; oxidative stress response; peroxidase