title: The small GTPase MoYpt7 is required for membrane fusion in autophagy and pathogenicity of Magnaporthe oryzae.
abstract: Rab GTPases are required for vesicle-vacuolar fusion during vacuolar biogenesis in fungi. To date, little is known about the biological functions of the Rab small GTPase components in Magnaporthe oryzae. In this study, we investigated MoYpt7 of M. oryzae, a homologue of the small Ras-like GTPase Ypt7 in Saccharomyces cerevisiae. Cellular localization assays showed that MoYpt7 was predominantly localized to vacuolar membranes. Using a targeted gene disruption strategy, a ΔMoYPT7 mutant was generated that exhibited defects in mycelial growth and production of conidia. The conidia of the ΔMoYPT7 mutant were malformed and defective in the formation of appressoria. Consequently, the ΔMoYPT7 mutant failed to cause disease in rice and barley. Furthermore, the ΔMoYPT7 mutant showed impairment in autophagy, breached cell wall integrity, and higher sensitivity to both calcium and heavy metal stress. Transformants constitutively expressing an active MoYPT7 allele (MoYPT7-CA, Gln67Leu) exhibited distinct phenotypes from the ΔMoYPT7 mutant. Expression of MoYPT7-CA in MoYpt7 reduced pathogenicity and produced more appressoria-forming single-septum conidia. These results indicate that MoYPT7 is required for fungal morphogenesis, vacuole fusion, autophagy, stress resistance and pathogenicity in M. oryzae.
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Liu
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
authors.forename: Si-Miao
authors.initials: SM
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy Sciences, Nanjing, 210008, China.
authors.forename: Hui-Min
authors.initials: HM
authors.lastname: Gao
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Guo-Ao
authors.initials: GA
authors.lastname: Ning
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Huan-Bin
authors.initials: HB
authors.lastname: Shi
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, 310058, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Dong
authors.affiliation: Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
authors.forename: Yao-Yao
authors.initials: YY
authors.lastname: Qi
authors.affiliation: Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
authors.forename: Guo-Dong
authors.initials: GD
authors.lastname: Lu
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.|Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
authors.forename: Zong-Hua
authors.initials: ZH
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, 310058, China.|China Tobacco Gene Research Center, Zhengzhou Tobacco Institute of CNTC, Zhengzhou, 450001, China.
authors.forename: Fu-Cheng
authors.initials: FC
authors.lastname: Lin
mesh_terms: D000595:Amino Acid Sequence; D001343:Autophagy / Q000235:genetics*; D002118:Calcium / Q000494:pharmacology; D002473:Cell Wall / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D001467:Hordeum / Q000382:microbiology; D020082:Magnaporthe / Q000235:genetics / Q000472:pathogenicity*; D008561:Membrane Fusion / Q000235:genetics* / Q000502:physiology; D019216:Metals, Heavy / Q000494:pharmacology; D008969:Molecular Sequence Data; D012275:Oryza / Q000382:microbiology; D010641:Phenotype; D010935:Plant Diseases / Q000382:microbiology; D012441:Saccharomyces cerevisiae / Q000235:genetics; D013172:Spores, Fungal / Q000235:genetics / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics; D014617:Vacuoles / Q000378:metabolism*; D014774:Virulence / Q000235:genetics; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D019216:Metals, Heavy; D020691:rab GTP-Binding Proteins; D002118:Calcium