The role of regulated protein degradation in auxin response

Plant Mol Biol. Jun-Jul 2002;49(3-4):401-9.


Auxin-regulated gene expression is mediated by two families of transcription factors. The ARF proteins bind to a conserved DNA sequence called the AuxRE and activate transcription. The Aux/IAA proteins repress ARF function, presumably by forming dimers with ARF proteins. Recent genetic studies in Arabidopsis indicate that auxin regulates this system by promoting the ubiquitin-mediated degradation of the Aux/IAA proteins, thus permitting ARF function. Mutations in components of SCF(TIR1), a ubiquitin protein ligase (E3) result in stabilization of Aux/IAA proteins and decreased auxin response. Further, recent biochemical experiments indicate that the Aux/IAA proteins bind SCF(TIR1) in an auxin-dependent manner.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Arabidopsis / drug effects
  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Cysteine Endopeptidases / metabolism
  • Gene Expression Regulation, Plant / drug effects
  • Indoleacetic Acids / metabolism
  • Indoleacetic Acids / pharmacology*
  • Models, Biological
  • Multienzyme Complexes / metabolism
  • Plant Proteins / metabolism*
  • Plants / drug effects*
  • Plants / genetics
  • Plants / metabolism
  • Proteasome Endopeptidase Complex
  • Protein Binding
  • Signal Transduction
  • Transcription Factors / metabolism
  • Ubiquitin / metabolism


  • Indoleacetic Acids
  • Multienzyme Complexes
  • Plant Proteins
  • Transcription Factors
  • Ubiquitin
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex