FT Protein Movement Contributes to Long-Distance Signaling in Floral Induction of Arabidopsis

@article{Corbesier2007FTPM,
  title={FT Protein Movement Contributes to Long-Distance Signaling in Floral Induction of Arabidopsis},
  author={Laurent Corbesier and Coral Vincent and Seonghoe Jang and Fabio Fornara and Qingzhi Fan and Iain Robert Searle and Antonis Giakountis and Sara Farrona and Lionel Gissot and Colin G N Turnbull and George Coupland},
  journal={Science},
  year={2007},
  volume={316},
  pages={1030 - 1033}
}
In plants, seasonal changes in day length are perceived in leaves, which initiate long-distance signaling that induces flowering at the shoot apex. The identity of the long-distance signal has yet to be determined. In Arabidopsis, activation of FLOWERING LOCUS T (FT) transcription in leaf vascular tissue (phloem) induces flowering. We found that FT messenger RNA is required only transiently in the leaf. In addition, FT fusion proteins expressed specifically in phloem cells move to the apex and… 
NaKR1 regulates long-distance movement of FLOWERING LOCUS T in Arabidopsis
TLDR
It is shown 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.
Regulation and identity of florigen: FLOWERING LOCUS T moves center stage.
TLDR
Progress in defining the molecular mechanisms that activate this module in response to changing day length and the increasing evidence that FT protein is a major component of florigen are described.
Long-distance, graft-transmissible action of Arabidopsis FLOWERING LOCUS T protein to promote flowering.
TLDR
This work shows that the FT activity, either from overexpressing or inducible transgenes or from the endogenous gene, to promote flowering is transmissible through a graft junction, and that an FT protein with a T7 tag is transported from a donor scion to the apical region of recipient stock plants and becomes detectable within a day or two.
The sugar transporter SWEET10 acts downstream of FLOWERING LOCUS T during floral transition of Arabidopsis thaliana
TLDR
The results suggest that the FT-signaling pathway activates the transcription of a sucrose uptake/efflux carrier during floral transition, indicating that it alters the metabolism of flowering plants as well as reprogramming the transcriptionof floral regulators in the shoot meristem.
Mobile FT mRNA contributes to the systemic florigen signalling in floral induction
TLDR
It is demonstrated that the Arabidopsis FT mRNA, independent of the FT protein, can move into the SAM, and the data suggest a possible role for FT mRNA in systemic floral signalling, and demonstrate that cis-transportation of cellular mRNA into SAM and meristem exclusion of pathogenic RNAs are two mechanistically distinct processes.
Leaf-produced floral signals.
  • J. Zeevaart
  • Environmental Science
    Current opinion in plant biology
  • 2008
Florigen trafficking integrates photoperiod and temperature signals in Arabidopsis.
TLDR
It is suggested that ambient temperatures regulate both FT mRNA expression and FT protein trafficking to prevent precocious flowering at low temperatures and ensure plant reproductive success under favorable environmental conditions.
Systemic movement of FT mRNA and a possible role in floral induction
TLDR
There is a promotion of flowering when increased levels of virally expressed FT mRNA are present together with endogenously produced FT protein in inducing conditions, even if the additional FT mRNA is non-translatable and thus not increasing the overall levels of FT protein.
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References

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TLDR
Data suggest that FT primarily controls the timing of flowering of Arabidopsis, and that integration of temporal and spatial information is mediated in part by the bZIP transcription factor FD, which is already expressed at the shoot apex before floral induction.
FD, a bZIP Protein Mediating Signals from the Floral Pathway Integrator FT at the Shoot Apex
FLOWERING LOCUS T (FT) is a conserved promoter of flowering that acts downstream of various regulatory pathways, including one that mediates photoperiodic induction through CONSTANS (CO), and is
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TLDR
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TLDR
It is proposed that, partly through the activation of FT, CO regulates the synthesis or transport of a systemic flowering signal, thereby positioning this signal within the established hierarchy of regulatory proteins that controls flowering.
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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