title: Suppression of tiller bud activity in tillering dwarf mutants of rice.
abstract: In this study, we analyzed five tillering dwarf mutants that exhibit reduction of plant stature and an increase in tiller numbers. We show that, in the mutants, axillary meristems are normally established but the suppression of tiller bud activity is weakened. The phenotypes of tillering dwarf mutants suggest that they play roles in the control of tiller bud dormancy to suppress bud activity. However, tillering dwarf mutants show the dependence of both node position and planting density on their growth, which implies that the functions of tillering dwarf genes are independent of the developmental and environmental control of bud activity. Map-based cloning of the D3 gene revealed that it encodes an F-box leucine-trich repeat (LRR) protein orthologous to Arabidopsis MAX2/ORE9. This indicates the conservation of mechanisms controlling axillary bud activity between monocots and eudicots. We suggest that tillering dwarf mutants are suitable for the study of bud activity control in rice and believe that future molecular and genetic studies using them may enable significant progress in understanding the control of tillering and shoot branching.
authors.affiliation: Graduate School of Agriculture and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, 113-8657 Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Masahiko
authors.initials: M
authors.lastname: Maekawa
authors.forename: Tomotsugu
authors.initials: T
authors.lastname: Arite
authors.forename: Kazumitsu
authors.initials: K
authors.lastname: Onishi
authors.forename: Itsuro
authors.initials: I
authors.lastname: Takamure
authors.forename: Junko
authors.initials: J
authors.lastname: Kyozuka
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development; D001483:Base Sequence; D002874:Chromosome Mapping; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D018519:Meristem / Q000033:anatomy & histology / Q000254:growth & development; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins