Cellular auxin homeostasis under high temperature is regulated through a sorting NEXIN1-dependent endosomal trafficking pathway

Plant Cell. 2013 Sep;25(9):3424-33. doi: 10.1105/tpc.113.115881. Epub 2013 Sep 3.

Abstract

High-temperature-mediated adaptation in plant architecture is linked to the increased synthesis of the phytohormone auxin, which alters cellular auxin homeostasis. The auxin gradient, modulated by cellular auxin homeostasis, plays an important role in regulating the developmental fate of plant organs. Although the signaling mechanism that integrates auxin and high temperature is relatively well understood, the cellular auxin homeostasis mechanism under high temperature is largely unknown. Using the Arabidopsis thaliana root as a model, we demonstrate that under high temperature, roots counterbalance the elevated level of intracellular auxin by promoting shootward auxin efflux in a PIN-FORMED2 (PIN2)-dependent manner. Further analyses revealed that high temperature selectively promotes the retrieval of PIN2 from late endosomes and sorts them to the plasma membrane through an endosomal trafficking pathway dependent on SORTING NEXIN1. Our results demonstrate that recycling endosomal pathway plays an important role in facilitating plants adaptation to increased temperature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological
  • Arabidopsis / cytology
  • Arabidopsis / genetics*
  • Arabidopsis / physiology
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism*
  • Cell Membrane / metabolism
  • Endosomes / metabolism
  • Genes, Reporter
  • Gravitropism
  • Homeostasis
  • Hot Temperature
  • Indoleacetic Acids / analysis
  • Indoleacetic Acids / metabolism*
  • Mutation
  • Plant Growth Regulators / analysis
  • Plant Growth Regulators / metabolism*
  • Plant Roots / cytology
  • Plant Roots / genetics
  • Plant Roots / physiology
  • Protein Transport
  • Recombinant Fusion Proteins
  • Seedlings / cytology
  • Seedlings / genetics
  • Seedlings / physiology
  • Signal Transduction
  • Sorting Nexins / genetics
  • Sorting Nexins / metabolism*

Substances

  • Arabidopsis Proteins
  • Indoleacetic Acids
  • PIN2 protein, Arabidopsis
  • Plant Growth Regulators
  • Recombinant Fusion Proteins
  • SNX1 protein, Arabidopsis
  • Sorting Nexins