Arabidopsis florigen FT binds to diurnally oscillating phospholipids that accelerate flowering.
Arabidopsis FT protein is a component of florigen, which transmits photoperiodic flowering signals from leaf companion cells to the shoot apex. Here, we show that FT specifically binds phosphatidylcholine (PC) in vitro. A transgenic approach to increase PC levels in vivo in the shoot meristem accelerates flowering whereas reduced PC levels delay flowering, demonstrating that PC levels are correlated with flowering time. The early flowering is related to FT activity, because expression of FT-effector genes is increased in these plants. Simultaneous increase of FT and PC in the shoot apical meristem further stimulates flowering, whereas a loss of FT function leads to an attenuation of the effect of increased PC. Specific molecular species of PC oscillate diurnally, and night-dominant species are not the preferred ligands of FT. Elevating night-dominant species during the day delays flowering. We suggest that FT binds to diurnally changing molecular species of PC to promote flowering.
1] Institute of Plant and Microbial Biology, Academia Sinica, 128 Section 2 Academia Road, Nankang, Taipei 11529, Taiwan [2] Max-Planck-Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, Cologne 50829, Germany [3] Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, Karlrobert-Kreiten-Strasse 13, Bonn 53115, Germany [4] Japan Science and Technology Agency, PRESTO, 4-8-1 Honcho, Kawaguchi, Saitama 332-0012, Japan.
Yuki
Y
Nakamura
Max-Planck-Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, Cologne 50829, Germany.
Fernando
F
Andrés
Institute of Plant and Microbial Biology, Academia Sinica, 128 Section 2 Academia Road, Nankang, Taipei 11529, Taiwan.
Kazue
K
Kanehara
Institute of Plant and Microbial Biology, Academia Sinica, 128 Section 2 Academia Road, Nankang, Taipei 11529, Taiwan.
Yu-chi
YC
Liu
Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, Karlrobert-Kreiten-Strasse 13, Bonn 53115, Germany.
Peter
P
Dörmann
Max-Planck-Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, Cologne 50829, Germany.
George
G
Coupland
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060405:Florigen / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D018519:Meristem / Q000235:genetics / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism*; D017440:Photoperiod; D011485:Protein Binding
D029681:Arabidopsis Proteins; C418905:FT protein, Arabidopsis; D060405:Florigen; D010713:Phosphatidylcholines