title: Trehalose 6-phosphate phosphatase is required for development, virulence and mycotoxin biosynthesis apart from trehalose biosynthesis in Fusarium graminearum.
abstract: Trehalose 6-phosphate synthase (TPS1) and trehalose 6-phosphate phosphatase (TPS2) are required for trehalose biosynthesis in yeast and filamentous fungi, including Fusarium graminearum. Three null mutants Δtps1, Δtps2 and Δtps1-Δtps2, each carrying either a single deletion of TPS1 or TPS2 or a double deletion of TPS1-TPS2, were generated from a toxigenic F. graminearum strain and were not able to synthesize trehalose. In contrast to its reported function in yeasts and filamentous fungi, TPS1 appeared dispensable for development and virulence. However, deletion of TPS2 abolished sporulation and sexual reproduction; it also altered cell polarity and ultrastructure of the cell wall in association with reduced chitin biosynthesis. The cell polarity alteration was exhibited as reduced apical growth and increased lateral growth and branching with increased hyphal and cell wall widths. Moreover, the TPS2-deficient strain displayed abnormal septum development and nucleus distribution in its conidia and vegetative hyphae. The Δtps2 mutant also had 62% lower mycelial growth on potato dextrose agar and 99% lower virulence on wheat compared with the wild-type. The Δtps1, Δtps2 and Δtps1-Δtps2 mutants synthesized over 3.08-, 7.09- and 2.47-fold less mycotoxins, respectively, on rice culture compared with the wild-type. Comparative transcriptome analysis revealed that the Δtps1, Δtps2 and Δtps1-Δtps2 mutants had 486, 1885 and 146 genotype-specific genes, respectively, with significantly changed expression profiles compared with the wild-type. Further dissection of this pathway will provide new insights into regulation of fungal development, virulence and trichothecene biosynthesis.
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Xiu-Shi
authors.initials: XS
authors.lastname: Song
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: He-Ping
authors.initials: HP
authors.lastname: Li
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Jing-Bo
authors.initials: JB
authors.lastname: Zhang
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Song
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Xiao-Min
authors.initials: XM
authors.lastname: Du
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: An-Dong
authors.initials: AD
authors.lastname: Gong
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Yi-Ke
authors.initials: YK
authors.lastname: Liu
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Yan-Ni
authors.initials: YN
authors.lastname: Feng
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Agboola
authors.affiliation: Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China; National Center of Plant Gene Research (Wuhan), Wuhan 430070, People's Republic of China. Electronic address: yucailiao@mail.hzau.edu.cn.
authors.forename: Yu-Cai
authors.initials: YC
authors.lastname: Liao
mesh_terms: D002473:Cell Wall / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D005670:Fusarium / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D015966:Gene Expression Regulation, Fungal; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism*; D025301:Hyphae / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D009154:Mutation; D009183:Mycotoxins / Q000096:biosynthesis* / Q000235:genetics; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism*; D013172:Spores, Fungal / Q000235:genetics / Q000378:metabolism; D014199:Trehalose / Q000096:biosynthesis* / Q000235:genetics; D014908:Triticum / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D009183:Mycotoxins; D014199:Trehalose; D005964:Glucosyltransferases; C023180:trehalose-6-phosphate synthase; C023178:trehalose-phosphatase; D010744:Phosphoric Monoester Hydrolases
keywords: Cell polarity; Development; Fusarium graminearum; Mycotoxin; Trehalose 6-phosphate phosphatase; Virulence