FCA mediates thermal adaptation of stem growth by attenuating auxin action in Arabidopsis.
Global warming is predicted to profoundly affect plant distribution and crop yield in the near future. Higher ambient temperature can influence diverse aspects of plant growth and development. In Arabidopsis, the basic helix-loop-helix transcription factor Phytochrome-Interacting Factor 4 (PIF4) regulates temperature-induced adaptive responses by modulating auxin biosynthesis. At high temperature, PIF4 directly activates expression of YUCCA8 (YUC8), a gene encoding an auxin biosynthetic enzyme, resulting in auxin accumulation. Here we demonstrate that the RNA-binding protein FCA attenuates PIF4 activity by inducing its dissociation from the YUC8 promoter at high temperature. At 28 °C, auxin content is elevated in FCA-deficient mutants that exhibit elongated stems but reduced in FCA-overexpressing plants that exhibit reduced stem growth. We propose that the FCA-mediated regulation of YUC8 expression tunes down PIF4-induced architectural changes to achieve thermal adaptation of stem growth at high ambient temperature.
Department of Chemistry, Seoul National University, Seoul 151-742, Korea.
Hyo-Jun
HJ
Lee
Department of Chemistry, Seoul National University, Seoul 151-742, Korea.
Jae-Hoon
JH
Jung
Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
Lucas
L
Cortés Llorca
Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
Sang-Gyu
SG
Kim
Department of Chemistry, Seoul National University, Seoul 151-742, Korea.
Sangmin
S
Lee
Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
Ian T
IT
Baldwin
1] Department of Chemistry, Seoul National University, Seoul 151-742, Korea [2] Plant Genomics and Breeding Institute, Seoul National University, Seoul 151-742, Korea.
Chung-Mo
CM
Park
D000222:Adaptation, Physiological / Q000502:physiology*; D017360:Arabidopsis / Q000254:growth & development / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000502:physiology*; D051792:Basic Helix-Loop-Helix Proteins / Q000502:physiology; D006358:Hot Temperature; D007210:Indoleacetic Acids / Q000378:metabolism*; D006899:Mixed Function Oxygenases / Q000502:physiology; D010937:Plant Growth Regulators / Q000502:physiology*; D018547:Plant Stems / Q000254:growth & development* / Q000502:physiology; D016601:RNA-Binding Proteins / Q000502:physiology*
D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D007210:Indoleacetic Acids; D006899:Mixed Function Oxygenases; D010937:Plant Growth Regulators; D016601:RNA-Binding Proteins; C106535:Flowering time control protein FCA, Arabidopsis; C459466:PIF4 protein, Arabidopsis; C585335:YUCCA8 protein, Arabidopsis