The COP9 signalosome: regulating plant development through the control of proteolysis

Annu Rev Plant Biol. 2003;54:165-82. doi: 10.1146/annurev.arplant.54.031902.134847.


The COP9 signalosome (CSN) is a multiprotein complex that was initially identified in plants as a repressor of photomorphogenesis. It is now known to play major roles in several other developmental pathways, from auxin response to flower development. Furthermore, the COP9 signalosome shares homologies with the lid sibcomplex of the proteasome and is evolutionarily conserved from fission yeast to humans. It is important for the proper development of virtually all higher eukaryotes. In recent years, significant progress has been made in unraveling the molecular, cellular, and physiological mode of action of the COP9 signalosome. This review discusses our current understanding of the COP9 signalosome function with particular emphasis on its recently defined role in modulating a wide variety of cellular processes by regulating specific protein degradation events.

Publication types

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

MeSH terms

  • COP9 Signalosome Complex
  • Cysteine Endopeptidases / metabolism
  • Multienzyme Complexes / metabolism
  • Multigene Family
  • Multiprotein Complexes
  • Peptide Hydrolases
  • Plant Development
  • Plant Physiological Phenomena
  • Plants / genetics
  • Plants / metabolism*
  • Proteasome Endopeptidase Complex
  • Proteins / metabolism
  • Proteins / physiology*
  • Signal Transduction / physiology*


  • Multienzyme Complexes
  • Multiprotein Complexes
  • Proteins
  • Peptide Hydrolases
  • COP9 Signalosome Complex
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex