Journal Article

Systems analysis of auxin transport in the Arabidopsis root apex

Bennett, Malcolm J, Reproduction et développement des plantes (RDP) ; École normale supérieure de Lyon (ENS de Lyon) ; Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Yun, Jeonga, Pearce, Simon P, Fozard, John A, Pridmore, Tony P, French, Andrew P, Physics Department ; Bard College at Simon’s Rock, Kramer, Eric, Institute of Molecular and Cellular Biology of Plants ; Universitat Politècnica de València = Universitad Politecnica de Valencia = Polytechnic University of Valencia (UPV), Wells, Darren M, Oh, Jaesung, Vernoux, Teva, Swarup, Ranjan, Hodgman, T. Charlie, Band, Leah R, Li, Wenda, Department of Genetics ; North Carolina State University [Raleigh] (NC State) ; University of North Carolina System (UNC)-University of North Carolina System (UNC), Biotechnology and Biological Sciences Research Council (BBSRC); Engineering and Physical Sciences Research Council; Lev

2014

Overview

Auxin is a key regulator of plant growth and development. Within the root tip, auxin distribution plays a crucial role specifying developmental zones and coordinating tropic responses. Determining how the organ-scale auxin pattern is regulated at the cellular scale is essential to understanding how these processes are controlled. In this study, we developed an auxin transport model based on actual root cell geometries and carrier subcellular localizations. We tested model predictions using the DII-VENUS auxin sensor in conjunction with state-of-the-art segmentation tools. Our study revealed that auxin efflux carriers alone cannot create the pattern of auxin distribution at the root tip and that AUX1/LAX influx carriers are also required. We observed that AUX1 in lateral root cap (LRC) and elongating epidermal cells greatly enhance auxin's shootward flux, with this flux being predominantly through the LRC, entering the epidermal cells only as they enter the elongation zone. We conclude that the nonpolar AUX1/LAX influx carriers control which tissues have high auxin levels, whereas the polar PIN carriers control the direction of auxin transport within these tissues.

• Publisher: American Society of Plant Biologists (ASPB),CCSD,American Society of Plant Biologists
• Subject: Arabidopsis - metabolism / Auxins / Biological Transport / Botanics / Development Biology / Epidermal cells / Indoleacetic Acids - metabolism / Large-Scale Biology / LARGE-SCALE BIOLOGY ARTICLE / Learning resources centers / Life Sciences / Modeling / Parametric models / Plant cells / Plant roots / Plant Roots - metabolism / Plants / Research design / Root tips / Subcellular Fractions - metabolism / Vegetal Biology
• ISBN: 0003349327000