Ntann12 annexin expression is induced by auxin in tobacco roots

J Exp Bot. 2011 Jul;62(11):4055-65. doi: 10.1093/jxb/err112. Epub 2011 May 4.

Abstract

Ntann12, encoding a polypeptide homologous to annexins, was found previously to be induced upon infection of tobacco with the bacterium Rhodococcus fascians. In this study, Ntann12 is shown to bind negatively charged phospholipids in a Ca(2+)-dependent manner. In plants growing in light conditions, Ntann12 is principally expressed in roots and the corresponding protein was mainly immunolocalized in the nucleus. Ntann12 expression was inhibited following plant transfer to darkness and in plants lacking the aerial part. However, an auxin (indole-3-acetic acid) treatment restored the expression of Ntann12 in the root system in dark conditions. Conversely, polar auxin transport inhibitors such as 1-naphthylphthalamic acid (NPA) or 2,3,5-triiodobenzoic acid (TIBA) inhibited Ntann12 expression in light condition. These results indicate that the expression of Ntann12 in the root is linked to the perception of a signal in the aerial part of the plant that is transmitted to the root via polar auxin transport.

MeSH terms

  • Annexins / metabolism*
  • Darkness
  • Indoleacetic Acids / antagonists & inhibitors
  • Indoleacetic Acids / pharmacology
  • Light
  • Nicotiana / growth & development
  • Nicotiana / metabolism*
  • Nicotiana / radiation effects
  • Phospholipids / metabolism
  • Phthalimides / pharmacology
  • Plant Growth Regulators / antagonists & inhibitors
  • Plant Growth Regulators / pharmacology
  • Plant Roots / growth & development
  • Plant Roots / metabolism*
  • Plant Roots / radiation effects
  • Signal Transduction*
  • Triiodobenzoic Acids / pharmacology

Substances

  • Annexins
  • Indoleacetic Acids
  • Phospholipids
  • Phthalimides
  • Plant Growth Regulators
  • Triiodobenzoic Acids
  • alpha-naphthylphthalamic acid
  • indoleacetic acid
  • 2,3,5-triiodobenzoic acid