An upstream regulator of the 26S proteasome modulates organ size in Arabidopsis thaliana

Plant J. 2013 Apr;74(1):25-36. doi: 10.1111/tpj.12097. Epub 2013 Mar 7.


In both animal and plant kingdoms, body size is a fundamental but still poorly understood attribute of biological systems. Here we report that the Arabidopsis NAC transcription factor 'Regulator of Proteasomal Gene Expression' (RPX) controls leaf size by positively modulating proteasome activity. We further show that the cis-element recognized by RPX is evolutionarily conserved between higher plant species. Upon over-expression of RPX, plants exhibit reduced growth, which may be reversed by a low concentration of the pharmacological proteasome inhibitor MG132. These data suggest that the rate of protein turnover during growth is a critical parameter for determining final organ size.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / growth & development
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • DNA, Bacterial
  • Gene Expression Regulation, Plant
  • Gene Knockout Techniques
  • Gene Regulatory Networks
  • Leupeptins
  • Mutagenesis, Insertional
  • Plant Leaves / growth & development*
  • Plant Roots / growth & development
  • Plants, Genetically Modified / growth & development
  • Promoter Regions, Genetic
  • Proteasome Endopeptidase Complex / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*


  • Arabidopsis Proteins
  • DNA, Bacterial
  • Leupeptins
  • T-DNA
  • Transcription Factors
  • Proteasome Endopeptidase Complex
  • ATP dependent 26S protease
  • benzyloxycarbonylleucyl-leucyl-leucine aldehyde