Ethylene regulates arabidopsis development via the modulation of DELLA protein growth repressor function.
Phytohormones regulate plant development via a poorly understood signal response network. Here, we show that the phytohormone ethylene regulates plant development at least in part via alteration of the properties of DELLA protein nuclear growth repressors, a family of proteins first identified as gibberellin (GA) signaling components. This conclusion is based on the following experimental observations. First, ethylene inhibited Arabidopsis root growth in a DELLA-dependent manner. Second, ethylene delayed the GA-induced disappearance of the DELLA protein repressor of ga1-3 from root cell nuclei via a constitutive triple response-dependent signaling pathway. Third, the ethylene-promoted "apical hook" structure of etiolated seedling hypocotyls was dependent on the relief of DELLA-mediated growth restraint. Ethylene, auxin, and GA responses now can be attributed to effects on DELLA function, suggesting that DELLA plays a key integrative role in the phytohormone signal response network.
Achard
Patrick
P
John Innes Centre, Norwich NR4 7UH, United Kingdom.
Vriezen
Wim H
WH
Van Der Straeten
Dominique
D
Harberd
Nicholas P
NP
D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D005030:Ethylenes / Q000494:pharmacology*; D018525:Germination / Q000502:physiology; D005875:Gibberellins / Q000494:pharmacology; D049452:Green Fluorescent Proteins; D007210:Indoleacetic Acids / Q000494:pharmacology; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D005810:Multigene Family; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; D005030:Ethylenes; C109555:GAI protein, Arabidopsis; D005875:Gibberellins; D007210:Indoleacetic Acids; D008164:Luminescent Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; C450824:RGL1 protein, Arabidopsis; C450823:RGL2 protein, Arabidopsis; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D049452:Green Fluorescent Proteins; C036216:ethylene; D011494:Protein Kinases; C477753:CTR1 protein, Arabidopsis