title: NaKR1 regulates long-distance movement of FLOWERING LOCUS T in Arabidopsis.
abstract: Flowering plants perceive photoperiodic signals in leaves to generate mobile stimuli required for the induction of flower formation at shoot apices. Although FLOWERING LOCUS T (FT) has been identified as part of the mobile floral stimuli in Arabidopsis thaliana, the mechanisms underlying long-distance movement of FT from leaves to shoot apices remain largely unclear. Here we show that a heavy-metal-associated (HMA) domain-containing protein, SODIUM POTASSIUM ROOT DEFECTIVE 1 (NaKR1), is activated by CONSTANS (CO) under long-day conditions and regulates long-distance movement of FT in Arabidopsis. Loss of function of NaKR1 compromises FT transport to shoot apices through sieve elements, causing late flowering under long-day conditions. NaKR1 and FT share similar expression patterns and subcellular localization, and interact with each other in vivo. Grafting experiments demonstrate that NaKR1 promotes flowering through mediating FT translocation from leaves to shoot apices. Thus, photoperiodic control of floral induction requires NaKR1-mediated long-distance delivery of florigenic signals.
authors.affiliation: Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Lu
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Lisha
authors.initials: L
authors.lastname: Shen
authors.affiliation: Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D018506:Gene Expression Regulation, Plant; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C092776:CONSTANS protein, Arabidopsis; D004268:DNA-Binding Proteins; C418905:FT protein, Arabidopsis; D014157:Transcription Factors