title: klavier (klv), a novel hypernodulation mutant of Lotus japonicus affected in vascular tissue organization and floral induction.
abstract: A novel hypernodulation mutant line was isolated from Lotus japonicus Miyakojima MG-20 by irradiation with a helium ion beam. This mutant, named klavier (klv), had roots that were densely covered with small nodules. The nodulation zone of klv was significantly wider than that of the wild type. Grafting experiments showed that klv is impaired in the long-distance shoot-to-root autoregulatory mechanism. Thus the shoot genotype was found to be responsible for the negative regulation of nodule development by KLV. Nodulation of klv showed a higher tolerance to nitrogen (KNO3) than the wild type, which is a common feature of hypernodulating mutants. In addition to an increased number of nodules, the klv mutant showed convex leaf veins on the adaxial leaf surface, markedly delayed flowering and dwarf phenotypes. Microscopic examination of the leaf veins revealed that they were discontinuous. Other phenotypes such as fasciated stems, increased number of flowers and bifurcated pistils were also frequently observed in the klv mutant. Among these phenotypes, hypernodulation, aberrant leaf vein formation and significantly delayed flowering were all linked in a monogenic and recessive manner, indicating that these phenotypes are caused by either a single mutation, or tightly linked mutations. KLV was mapped within 0.29 cM on the long arm of chromosome 1.
authors.affiliation: Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Tokyo 113-0033, Japan.
authors.forename: Erika
authors.initials: E
authors.lastname: Oka-Kira
authors.forename: Kumiko
authors.initials: K
authors.lastname: Tateno
authors.forename: Kin-ichiro
authors.initials: K
authors.lastname: Miura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Haga
authors.forename: Masaki
authors.initials: M
authors.lastname: Hayashi
authors.forename: Kyuya
authors.initials: K
authors.lastname: Harada
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Naoya
authors.initials: N
authors.lastname: Shikazono
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tanaka
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Izumi
authors.initials: I
authors.lastname: Fukuhara
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nagata
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawaguchi
mesh_terms: D035264:Flowers / Q000235:genetics* / Q000254:growth & development*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D000070116:Lotus / Q000166:cytology / Q000235:genetics* / Q000254:growth & development*; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D018515:Plant Leaves / Q000033:anatomy & histology / Q000235:genetics; D018517:Plant Roots / Q000033:anatomy & histology* / Q000235:genetics* / Q000254:growth & development