title: The florigen genes FT and TSF modulate lateral shoot outgrowth in Arabidopsis thaliana.
abstract: Successful sexual reproduction of a plant with prolific seed production requires appropriate timing of flowering and concomitant change of architecture (e.g. internode elongation and branching) to facilitate production of the optimal number of flowers while enabling continued resource production through photosynthesis. Florigen is the prime candidate for a signal linking the two processes. Growth analysis of lateral shoots in mutants of FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) revealed a delay in the onset of outgrowth and a reduction of the growth rate in ft plants in long-day (LD) conditions and in tsf plants in short-day (SD) conditions. Thus, as in the case of floral transition, FT and TSF play dominant roles in LD and SD conditions, respectively, in the promotion of lateral shoot development. Differential expression patterns of the two genes were in good agreement with their differential roles both in the floral transition and in lateral shoot development under contrasting photoperiod conditions. By manipulating florigen production after bolting of the primary shoot, it was shown that florigen promotes lateral shoot growth independently of its effect on the floral transition of the primary shoot. Analysis of growth and gene expression in lateral shoots of the mutants suggests that the loss of florigen leads to a reduced rate of flower formation on lateral shoots. Together, we propose that the two florigen genes are an important key to linking the floral transition and lateral shoot development to maximize the reproductive success of a plant.
authors.affiliation: Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, 606-8501 Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Hiraoka
authors.forename: Ayako
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: Mitsutomo
authors.initials: M
authors.lastname: Abe
authors.forename: Takashi
authors.initials: T
authors.lastname: Araki
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D060405:Florigen / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D006358:Hot Temperature; D056626:Inflorescence / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018519:Meristem / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D009154:Mutation; D009928:Organ Specificity; D010641:Phenotype; D049488:Phosphatidylethanolamine Binding Protein / Q000235:genetics* / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; C418905:FT protein, Arabidopsis; D060405:Florigen; D049488:Phosphatidylethanolamine Binding Protein; D010937:Plant Growth Regulators; C500577:TSF protein, Arabidopsis