title: MoLys2 is necessary for growth, conidiogenesis, lysine biosynthesis, and pathogenicity in Magnaporthe oryzae.
abstract: Amino acid biosyntheses are complex but essential processes in growth and differentiation of eukaryotic cells. In the budding yeast Saccharomyces cerevisiae, the lysine biosynthesis via the α-aminoadipate (AA) pathway involves several steps, including reduction of AA to AA 6-semialdehyde by AA reductase ScLys2. In filamentous fungus Penicillium chrysogenum, disruption of the LYS2 gene blocked the lysine biosynthesis but promoted the production of the secondary metabolite penicillin. In comparison, little is known about the function of AA reductase Lys2 in phytopathogenic fungi. We here characterized the functions of MoLys2, a homolog of ScLys2, from the rice blast fungus Magnaporthe oryzae. Our results showed that the ΔMolys2 mutants were auxotrophic for lysine. The ΔMolys2 mutants also exhibited drastic reduction in pathogenicity on rice, inducing small disease lesions. Microscopic examination of the lesions revealed that the invasive hyphae of ΔMolys2 mutants were mostly restricted to the primary infected leaf sheath cells. In addition, exogenous lysine restored the production of conidia and near wild-type appressoria differentiation, and rescued the defect of pathogenicity in conidia infection of detached barely and rice leaf sheath. Our results indicated that MoLys2 is necessary for lysine biosynthesis that affects growth, conidiogenesis, and pathogenicity of the fungus. This study does implicate the potential for targeting lysine biosynthesis for the development of novel fungicides against M. oryzae.
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Rongfang
authors.initials: R
authors.lastname: Zuo
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Mengying
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Yanhan
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Ru
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China. Electronic address: zhgzhang@njau.edu.cn.
authors.forename: Zhengguang
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D025301:Hyphae / Q000254:growth & development; D008239:Lysine / Q000096:biosynthesis*; D020082:Magnaporthe / Q000254:growth & development / Q000472:pathogenicity / Q000502:physiology*; D012275:Oryza / Q000382:microbiology*; D013172:Spores, Fungal / Q000254:growth & development*
chemical_list: D005656:Fungal Proteins; D008239:Lysine
keywords: Growth; Lysine biosynthesis; MoLys2; Pathogenicity