title: Photomorphogenetic characteristics are severely affected in nucleoside diphosphate kinase-1 (ndk-1)-disrupted mutants in Neurospora crassa.
abstract: We previously demonstrated that the NDK-1 (Nucleoside Diphosphate Kinase-1) point mutant, ndk-1(P72H), displays a defective phenotype in light-induced perithecial polarity in Neurospora crassa. To investigate the biological function of NDK-1 in detail, we isolated two ndk-1 mutants, ndk-1(RIP-1) and ndk-1(RIP-2), using the RIPing (repeat induced point mutation) method. Notably, we detected no accumulation of ndk-1(RIP-1) mRNA and truncated NDK-1(RIP-2) protein. The ndk-1(RIP) mutants exhibited altered morphogenesis; (1) aerial hypha was not formed with no conidium formation, (2) the mutants exhibited colonial, and very slow mycelial growth on a solid medium and by shaking culture in a liquid medium, (3) light-induced carotenoid accumulation in mutant mycelia is reduced to less than half that by wild type, (4) the mutants exhibited spiral growth of mycelia, and (5) female sterility with defective protoperithecium formation. The morphogenetic processes of 1, 3, and 5 are light induced in the wild type. Moreover, despite only 10-20% of total nucleoside diphosphate kinase activity, the accumulation of relevant transcripts in the ndk-1(RIP) mutants, such as al-1 and al-2, was similar to that of wild type.
authors.affiliation: Graduate School of Integrated Science, Yokohama City University, 641-12 Maioka-cho, Yokohama 244-0813, Japan.
authors.forename: Bumkyu
authors.initials: B
authors.lastname: Lee
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Kohji
authors.initials: K
authors.lastname: Hasunuma
mesh_terms: D001483:Base Sequence; D002338:Carotenoids / Q000096:biosynthesis / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009492:Neurospora crassa / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D009701:Nucleoside-Diphosphate Kinase / Q000235:genetics*; D017354:Point Mutation
chemical_list: D005656:Fungal Proteins; D002338:Carotenoids; D009701:Nucleoside-Diphosphate Kinase