The ubiquitin/26S proteasome pathway, the complex last chapter in the life of many plant proteins

Trends Plant Sci. 2003 Mar;8(3):135-42. doi: 10.1016/S1360-1385(03)00014-1.


Plants use a repertoire of methods to control the level and activity of their constituent proteins. One method, whose prominence is only now being appreciated, is selective protein breakdown by the ubiquitin/26S proteasome pathway. Remarkably, recent analyses of the near-complete Arabidopsis thaliana genome identified >1300 genes, or approximately 5% of the proteome, involved in the ubiquitin/26S proteasome pathway, making it one of the most elaborate regulatory mechanisms in plants. Molecular genetic analyses have also connected individual components to almost all aspects of plant biology, including the cell-cycle, embryogenesis, photomorphogenesis, circadian rhythms, hormone signaling, homeosis, disease resistance and senescence. Consequently, it appears that the ubiquitin/26S proteasome pathway rivals transcription complexes and protein kinase cascades as the main player in plant cell regulation.

Publication types

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

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Cysteine Endopeptidases / chemistry
  • Cysteine Endopeptidases / genetics
  • Cysteine Endopeptidases / metabolism
  • Genome, Plant*
  • Multienzyme Complexes / chemistry
  • Multienzyme Complexes / genetics
  • Multienzyme Complexes / metabolism
  • Peptide Hydrolases / chemistry
  • Peptide Hydrolases / genetics*
  • Peptide Hydrolases / metabolism
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Proteasome Endopeptidase Complex
  • Protein Conformation
  • Ubiquitin / genetics*
  • Ubiquitin / metabolism


  • Multienzyme Complexes
  • Plant Proteins
  • Ubiquitin
  • Peptide Hydrolases
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex
  • ATP dependent 26S protease