title: The Sch9 kinase regulates conidium size, stress responses, and pathogenesis in Fusarium graminearum.
abstract: Fusarium head blight caused by Fusarium graminearum is an important disease of wheat and barley worldwide. In a previous study on functional characterization of the F. graminearum kinome, one protein kinase gene important for virulence is orthologous to SCH9 that is functionally related to the cAMP-PKA and TOR pathways in the budding yeast. In this study, we further characterized the functions of FgSCH9 in F. graminearum and its ortholog in Magnaporthe oryzae. The ΔFgsch9 mutant was slightly reduced in growth rate but significantly reduced in conidiation, DON production, and virulence on wheat heads and corn silks. It had increased tolerance to elevated temperatures but became hypersensitive to oxidative, hyperosmotic, cell wall, and membrane stresses. The ΔFgsch9 deletion also had conidium morphology defects and produced smaller conidia. These results suggest that FgSCH9 is important for stress responses, DON production, conidiogenesis, and pathogenesis in F. graminearum. In the rice blast fungus Magnaporthe oryzae, the ΔMosch9 mutant also was defective in conidiogenesis and pathogenesis. Interestingly, it also produced smaller conidia and appressoria. Taken together, our data indicate that the SCH9 kinase gene may have a conserved role in regulating conidium size and plant infection in phytopathogenic ascomycetes.
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Daipeng
authors.initials: D
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, United States of America.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China.
authors.forename: Yulin
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China; Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, United States of America.
authors.forename: Jin-Rong
authors.initials: JR
authors.lastname: Xu
mesh_terms: D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005670:Fusarium / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*; D017353:Gene Deletion; D001467:Hordeum / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D013172:Spores, Fungal / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D014908:Triticum / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D011494:Protein Kinases; C071569:SCH9 protein kinase