|
|
||||||||
|
First published online February 22, 2005; 10.1104/pp.104.053967 Plant Physiology 137:998-1008 (2005) © 2005 American Society of Plant Biologists Ethylene-Induced Differential Growth of Petioles in Arabidopsis. Analyzing Natural Variation, Response Kinetics, and Regulation1Plant Ecophysiology, Utrecht University, 3584 CA Utrecht, The Netherlands
Plants can reorient their organs in response to changes in environmental conditions. In some species, ethylene can induce resource-directed growth by stimulating a more vertical orientation of the petioles (hyponasty) and enhanced elongation. In this study on Arabidopsis (Arabidopsis thaliana), we show significant natural variation in ethylene-induced petiole elongation and hyponastic growth. This hyponastic growth was rapidly induced and also reversible because the petioles returned to normal after ethylene withdrawal. To unravel the mechanisms behind the natural variation, two contrasting accessions in ethylene-induced hyponasty were studied in detail. Columbia-0 showed a strong hyponastic response to ethylene, whereas this response was almost absent in Landsberg erecta (Ler). To test whether Ler is capable of showing hyponastic growth at all, several signals were applied. From all the signals applied, only spectrally neutral shade (20 µmol m2 s1) could induce a strong hyponastic response in Ler. Therefore, Ler has the capacity for hyponastic growth. Furthermore, the lack of ethylene-induced hyponastic growth in Ler is not the result of already-saturating ethylene production rates or insensitivity to ethylene, as an ethylene-responsive gene was up-regulated upon ethylene treatment in the petioles. Therefore, we conclude that Ler is missing an essential component between the primary ethylene signal transduction chain and a downstream part of the hyponastic growth signal transduction pathway.
1 This work was supported by the Dutch Science Foundation (PIONIER grant no. 80084470). Article, publication date, and citation information can be found at www.plantphysiol.org/cgi/doi/10.1104/pp.104.053967. * Corresponding author; e-mail f.f.millenaar{at}bio.uu.nl; fax 31302518366. Received September 24, 2004; returned for revision December 3, 2004; accepted December 3, 2004. This article has been cited by other articles:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ASPB Publications | PLANT PHYSIOLOGY® | THE PLANT CELL | |
|---|---|---|---|