title: WetA is required for conidiogenesis and conidium maturation in the ascomycete fungus Fusarium graminearum.
abstract: Fusarium graminearum, a prominent fungal pathogen that infects major cereal crops, primarily utilizes asexual spores to spread disease. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we functionally characterized the F. graminearum ortholog of Aspergillus nidulans wetA, which has been shown to be involved in conidiogenesis and conidium maturation. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidial dormancy by suppressing microcycle conidiation in F. graminearum. Transcriptome analyses demonstrated that most of the putative conidiation-related genes are expressed constitutively and that only a few genes are specifically involved in F. graminearum conidiogenesis. The conserved and distinct roles identified for WetA in F. graminearum provide new insights into the genetics of conidiation in filamentous fungi.
authors.affiliation: Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, Seoul National University, Seoul, Republic of Korea.
authors.forename: Hokyoung
authors.initials: H
authors.lastname: Son
authors.forename: Myung-Gu
authors.initials: MG
authors.lastname: Kim
authors.forename: Kyunghun
authors.initials: K
authors.lastname: Min
authors.forename: Jae Yun
authors.initials: JY
authors.lastname: Lim
authors.forename: Gyung Ja
authors.initials: GJ
authors.lastname: Choi
authors.forename: Jin-Cheol
authors.initials: JC
authors.lastname: Kim
authors.forename: Suhn-Kee
authors.initials: SK
authors.lastname: Chae
authors.forename: Yin-Won
authors.initials: YW
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D001343:Autophagy; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005670:Fusarium / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D005800:Genes, Fungal; D018869:Heat-Shock Response; D008969:Molecular Sequence Data; D025282:Mycelium / Q000166:cytology / Q000254:growth & development; D018384:Oxidative Stress; D010641:Phenotype; D017384:Sequence Deletion; D013172:Spores, Fungal / Q000166:cytology / Q000254:growth & development; D059467:Transcriptome; D014774:Virulence / Q000235:genetics
chemical_list: D005656:Fungal Proteins