Petersson, Sara
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
Abstract
Local concentration gradients of the plant growth regulator auxin (indole-3-acetic acid [IAA]) are thought to instruct the positioning of organ primordia and stem cell niches and to direct cell division, expansion, and differentiation. High-resolution measurements of endogenous IAA concentrations in support of the gradient hypothesis are required to substantiate this hypothesis. Here, we introduce fluorescence-activated cell sorting of green fluorescent protein-marked cell types combined with highly sensitive mass spectrometry methods as a novel means for analyses of IAA distribution and metabolism at cellular resolution. Our results reveal the presence of IAA concentration gradients within the Arabidopsis thaliana root tip with a distinct maximum in the organizing quiescent center of the root apex. We also demonstrate that the root apex provides an important source of IAA and that cells of all types display a high synthesis capacity, suggesting a substantial contribution of local biosynthesis to auxin homeostasis in the root tip. Our results indicate that local biosynthesis and polar transport combine to produce auxin gradients and maxima in the root tip.
Published in
Plant Cell
2009, volume: 21, number: 6, pages: 1659-1668
SLU Authors
Johansson, Annika
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
Kowalczyk, Mariusz
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
Makoveychuk, Alexander
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
Moritz, Thomas
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
Ljung, Karin
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
UKÄ Subject classification
Forest Science
Publication identifier
- DOI: https://doi.org/10.1105/tpc.109.066480
Permanent link to this page (URI)
https://res.slu.se/id/publ/26859