Auxin modulates the enhanced development of root hairs in Arabidopsis thaliana (L.) Heynh. under elevated CO(2)

Plant Cell Environ. 2011 Aug;34(8):1304-17. doi: 10.1111/j.1365-3040.2011.02330.x. Epub 2011 May 16.

Abstract

Root hairs may play a critical role in nutrient acquisition of plants grown under elevated CO(2) . This study investigated how elevated CO(2) enhanced the development of root hairs in Arabidopsis thaliana (L.) Heynh. The plants under elevated CO(2) (800 µL L(-1)) had denser and longer root hairs, and more H-positioned cells in root epidermis than those under ambient CO(2) (350 µL L(-1)). The elevated CO(2) increased auxin production in roots. Under elevated CO(2) , application of either 1-naphthoxyacetic acid (1-NOA) or N-1-naphthylphthalamic acid (NPA) blocked the enhanced development of root hairs. The opposite was true when the plants under ambient CO(2) were treated with 1-naphthylacetic acid (NAA), an auxin analogue. Furthermore, the elevated CO(2) did not enhance the development of root hairs in auxin-response mutants, axr1-3, and auxin-transporter mutants, axr4-1, aux1-7 and pin1-1. Both elevated CO(2) and NAA application increased expressions of caprice, triptychon and rho-related protein from plants 2, and decreased expressions of werewolf, GLABRA2, GLABRA3 and the transparent testa glabra 1, genes related to root-hair development, while 1-NOA and NPA application had an opposite effect. Our study suggests that elevated CO(2) enhanced the development of root hairs in Arabidopsis via the well-characterized auxin signalling and transport that modulate the initiation of root hairs and the expression of its specific genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / growth & development*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Carbon Dioxide / pharmacology*
  • DNA-Binding Proteins / genetics
  • Gene Expression Regulation, Plant
  • Glycolates / pharmacology
  • Homeodomain Proteins / genetics
  • Indoleacetic Acids / metabolism*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Mutation
  • Naphthaleneacetic Acids / pharmacology
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Phthalimides / pharmacology
  • Plant Epidermis / cytology
  • Plant Epidermis / drug effects
  • Plant Roots / drug effects
  • Plant Roots / growth & development*
  • Plant Roots / metabolism
  • Proto-Oncogene Proteins c-myb / genetics
  • Signal Transduction
  • Transcription Factors

Substances

  • AXR1 protein, Arabidopsis
  • AXR3 protein, Arabidopsis
  • Arabidopsis Proteins
  • Basic Helix-Loop-Helix Transcription Factors
  • CPC protein, Arabidopsis
  • DNA-Binding Proteins
  • GL2 protein, Arabidopsis
  • GL3 protein, Arabidopsis
  • Glycolates
  • Homeodomain Proteins
  • Indoleacetic Acids
  • Membrane Transport Proteins
  • Naphthaleneacetic Acids
  • Nuclear Proteins
  • PIN1 protein, Arabidopsis
  • Phthalimides
  • Proto-Oncogene Proteins c-myb
  • TRIPTYCHON protein, Arabidopsis
  • TTG1 protein, Arabidopsis
  • Transcription Factors
  • WER protein, Arabidopsis
  • Carbon Dioxide
  • alpha-naphthylphthalamic acid
  • 1-naphthaleneacetic acid
  • 1-naphthoxyacetic acid