The COP9 Signalosome Is Essential for Development of Drosophila Melanogaster

Curr Biol. 1999 Oct 21;9(20):1187-90. doi: 10.1016/S0960-9822(00)80023-8.


The COP9 signalosome (originally described as the COP9 complex) is an essential multi-subunit repressor of light-regulated development in plants [1] [2]. It has also been identified in mammals, though its role remains obscure [3] [4] [5]. This complex is similar to the regulatory lid of the proteasome and eIF3 [5] [9] [10] [11] [12] and several of its subunits are known to be involved in kinase signaling pathways [4] [6] [7] [8]. No proteins homologous to COP9 signalosome components were identified in the Saccharomyces cerevisiae genome, suggesting that the COP9 signalosome is specific for multi-cellular differentiation [13]. In order to reveal the developmental function of the COP9 signalosome in animals, we have isolated Drosophila melanogaster genes encoding eight subunits of the COP9 signalosome, and have shown by co-immunoprecipitation and gel-filtration analysis that these proteins are components of the Drosophila COP9 signalosome. Yeast two-hybrid assays indicated that several of these proteins interact, some through the PCI domain. Disruption of one of the subunits by either a P-element insertion or deletion of the gene caused lethality at the late larval or pupal stages. This lethality is probably a result of numerous pleiotropic effects. Our results indicate that the COP9 signalosome is conserved in invertebrates and that it has an essential role in animal development.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arabidopsis / genetics
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism
  • COP9 Signalosome Complex
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / growth & development*
  • Drosophila melanogaster / metabolism*
  • Genes, Insect
  • Insect Proteins / chemistry
  • Insect Proteins / genetics
  • Insect Proteins / metabolism*
  • Multiprotein Complexes
  • Peptide Hydrolases
  • Plant Proteins / chemistry
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Protein Structure, Quaternary
  • Proteins*
  • Signal Transduction
  • Species Specificity
  • Two-Hybrid System Techniques


  • Insect Proteins
  • Multiprotein Complexes
  • Plant Proteins
  • Proteins
  • Peptide Hydrolases
  • COP9 Signalosome Complex