title: Involvement of BcStr2 in methionine biosynthesis, vegetative differentiation, multiple stress tolerance and virulence in Botrytis cinerea.
abstract: The Str2 gene encodes a cystathionine γ-synthase that is a key enzyme in methionine (Met) biosynthesis in Saccharomyces cerevisiae. Met plays a critical role in protein synthesis and diverse cellular processes in both eukaryotes and prokaryotes. In this study, we characterized the Str2 orthologue gene BcStr2 in Botrytis cinerea. The BcStr2 mutant was unable to grow on minimal medium (MM). In addition, conidia of the mutant were unable to germinate in water-agar medium within 15 h of incubation. Supplementation with 1 mm Met or 0.5 mg/mL homocysteine, but not 1 mm cysteine or 0.5 mg/mL glutathione, rescued the defect in mycelial growth of the BcStr2 deletion mutant. These results indicate that the enzyme encoded by BcStr2 is involved in the conversion of cysteine into homocysteine. The mutant exhibited decreased conidiation and impaired sclerotium development. In addition, the BcStr2 mutant exhibited increased sensitivity to osmotic and oxidative stresses, cell wall-damaging agents and thermal stress. The mutant demonstrated dramatically decreased virulence on host plant tissues. All of the defects were restored by genetic complementation of the mutant with wild-type BcStr2. Taken together, the results of this study indicate that BcStr2 plays a critical role in the regulation of various cellular processes in B. cinerea.
authors.affiliation: College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Wenyong
authors.initials: W
authors.lastname: Shao
authors.affiliation: College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Yalan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Chiyuan
authors.initials: C
authors.lastname: Lv
authors.affiliation: College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Weichao
authors.initials: W
authors.lastname: Ren
authors.affiliation: College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
authors.forename: Changjun
authors.initials: C
authors.lastname: Chen
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000935:Antifungal Agents / Q000494:pharmacology; D053898:Biosynthetic Pathways / Q000187:drug effects; D020171:Botrytis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D018553:Cucumis sativus / Q000187:drug effects / Q000382:microbiology; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D008715:Methionine / Q000096:biosynthesis*; D009995:Osmosis / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D018515:Plant Leaves / Q000187:drug effects / Q000382:microbiology; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013172:Spores, Fungal / Q000187:drug effects / Q000254:growth & development; D013312:Stress, Physiological / Q000187:drug effects; D014774:Virulence / Q000187:drug effects
chemical_list: D000935:Antifungal Agents; D005656:Fungal Proteins; D008715:Methionine
keywords: BcStr2; Botrytis cinerea; methionine biosynthesis; virulence