Gene Symbol: COP8
Description: Proteasome component (PCI) domain protein
Species: thale cress

Top Publications

  1. Rubio V, Shen Y, Saijo Y, Liu Y, Gusmaroli G, Dinesh Kumar S, et al. An alternative tandem affinity purification strategy applied to Arabidopsis protein complex isolation. Plant J. 2005;41:767-78 pubmed
    ..Taken together, the data demonstrate the suitability of the TAPa system to allow efficient multi-protein complex isolation from stably transformed Arabidopsis. ..
  2. Dohmann E, Levesque M, Isono E, Schmid M, Schwechheimer C. Auxin responses in mutants of the Arabidopsis CONSTITUTIVE PHOTOMORPHOGENIC9 signalosome. Plant Physiol. 2008;147:1369-79 pubmed publisher
    ..Whether the CSN5 monomer, which is maintained in csn mutants such as csn3 or csn4, has a functional role, remains to be established...
  3. Gusmaroli G, Figueroa P, Serino G, Deng X. Role of the MPN subunits in COP9 signalosome assembly and activity, and their regulatory interaction with Arabidopsis Cullin3-based E3 ligases. Plant Cell. 2007;19:564-81 pubmed
    ..This study thus completes the genetic analysis of all CSN subunits and confirms the structural interdependence between PCI and MPN subunits in functional CSN complex formation. ..
  4. Serino G, Su H, Peng Z, Tsuge T, Wei N, Gu H, et al. Characterization of the last subunit of the Arabidopsis COP9 signalosome: implications for the overall structure and origin of the complex. Plant Cell. 2003;15:719-31 pubmed
    ..Comparative analyses of the subunit interaction of CSN revealed a set of conserved subunit contacts and resulted in a model of CSN subunit topology, some aspects of which were substantiated by in vivo cross-link tests. ..
  5. Serino G, Tsuge T, Kwok S, Matsui M, Wei N, Deng X. Arabidopsis cop8 and fus4 mutations define the same gene that encodes subunit 4 of the COP9 signalosome. Plant Cell. 1999;11:1967-80 pubmed
    ..complex-eIF3 domain protein encoded by a gene that maps to chromosome 5, near the chromosomal location of the cop8 and fus4 mutations...
  6. Feng S, Ma L, Wang X, Xie D, Dinesh Kumar S, Wei N, et al. The COP9 signalosome interacts physically with SCF COI1 and modulates jasmonate responses. Plant Cell. 2003;15:1083-94 pubmed
    ..Furthermore, we showed that both COI1 and CSN are essential for modulating the expression of genes in most cellular pathways responsive to JA. Thus, CSN and SCF(COI1) work together to control genome expression and promote JA responses. ..
  7. Gusmaroli G, Feng S, Deng X. The Arabidopsis CSN5A and CSN5B subunits are present in distinct COP9 signalosome complexes, and mutations in their JAMM domains exhibit differential dominant negative effects on development. Plant Cell. 2004;16:2984-3001 pubmed
    ..The initial characterization of CSN5A and CSN5B insertion mutants further supports these findings and provides genetic evidence on their unequal role in plant development. ..
  8. Chen H, Shen Y, Tang X, Yu L, Wang J, Guo L, et al. Arabidopsis CULLIN4 Forms an E3 Ubiquitin Ligase with RBX1 and the CDD Complex in Mediating Light Control of Development. Plant Cell. 2006;18:1991-2004 pubmed
    ..Thus, this study suggests a biochemical activity connection between CSN and CDD complexes in their cooperation with COP1 in orchestrating the repression of photomorphogenesis. ..
  9. Huang H, Quint M, Gray W. The eta7/csn3-3 auxin response mutant of Arabidopsis defines a novel function for the CSN3 subunit of the COP9 signalosome. PLoS ONE. 2013;8:e66578 pubmed publisher
    ..We hypothesize that in addition to its role in the CSN as a cullin deneddylase, CSN3 functions in a distinct protein complex that is required for proper auxin signaling. ..

More Information


  1. Wang X, Li W, Piqueras R, Cao K, Deng X, Wei N. Regulation of COP1 nuclear localization by the COP9 signalosome via direct interaction with CSN1. Plant J. 2009;58:655-67 pubmed publisher
    ..This study advances our understanding of COP1 localization, and the molecular interactions between COP1 and CSN. ..
  2. Spoel S, Mou Z, Tada Y, Spivey N, Genschik P, Dong X. Proteasome-mediated turnover of the transcription coactivator NPR1 plays dual roles in regulating plant immunity. Cell. 2009;137:860-72 pubmed publisher
    ..These in vivo data demonstrate dual roles for coactivator turnover in both preventing and stimulating gene transcription to regulate plant immunity. ..
  3. Kim T, Kim B, Yahalom A, Chamovitz D, von Arnim A. Translational regulation via 5' mRNA leader sequences revealed by mutational analysis of the Arabidopsis translation initiation factor subunit eIF3h. Plant Cell. 2004;16:3341-56 pubmed
  4. Wang X, Kang D, Feng S, Serino G, Schwechheimer C, Wei N. CSN1 N-terminal-dependent activity is required for Arabidopsis development but not for Rub1/Nedd8 deconjugation of cullins: a structure-function study of CSN1 subunit of COP9 signalosome. Mol Biol Cell. 2002;13:646-55 pubmed
    ..We conclude that CSN1 N-terminal domain is not required for the Rub1/Nedd8 deconjugation activity of cullins, but contributes to a significant aspect of CSN functions that are essential for plant development. ..
  5. Suzuki G, Yanagawa Y, Kwok S, Matsui M, Deng X. Arabidopsis COP10 is a ubiquitin-conjugating enzyme variant that acts together with COP1 and the COP9 signalosome in repressing photomorphogenesis. Genes Dev. 2002;16:554-9 pubmed
    ..Our data indicates that COP10 defines a possible E2 activity, thus validating the working hypothesis that the pleiotropic COP/DET/FUS group of proteins defined a protein ubiquitination pathway. ..
  6. Paz Aviram T, Yahalom A, Chamovitz D. Arabidopsis eIF3e interacts with subunits of the ribosome, Cop9 signalosome and proteasome. Plant Signal Behav. 2008;3:409-11 pubmed
    ..These interactions mesh well with our recent results which showed that eIF3e is degraded in a CSN-dependent, proteasome-dependent fashion, and inhibits translation when present in excess. ..
  7. Karniol B, Chamovitz D. The COP9 signalosome: from light signaling to general developmental regulation and back. Curr Opin Plant Biol. 2000;3:387-93 pubmed
    ..The COP9 complex is essential for animal development. The COP9 signalosome may have both an evolutionary and a physical relationship with both the regulatory lid of the proteasome and eIF3. ..
  8. Wang X, Feng S, Nakayama N, Crosby W, Irish V, Deng X, et al. The COP9 signalosome interacts with SCF UFO and participates in Arabidopsis flower development. Plant Cell. 2003;15:1071-82 pubmed
    ..We conclude that CSN is an essential regulator of Arabidopsis flower development and suggest that CSN regulates Arabidopsis flower development in part by modulating SCF(UFO)-mediated AP3 activation. ..
  9. Nakasone A, Fujiwara M, Fukao Y, Biswas K, Rahman A, Kawai Yamada M, et al. SMALL ACIDIC PROTEIN1 acts with RUB modification components, the COP9 signalosome, and AXR1 to regulate growth and development of Arabidopsis. Plant Physiol. 2012;160:93-105 pubmed publisher
    ..Our findings suggest that SMAP1 is involved in the auxin response and possibly in other cullin-RING ubiquitin ligase-regulated signaling processes via its interaction with components associated with RELATED TO UBIQUITIN modification. ..
  10. Dohmann E, Levesque M, De Veylder L, Reichardt I, Jurgens G, Schmid M, et al. The Arabidopsis COP9 signalosome is essential for G2 phase progression and genomic stability. Development. 2008;135:2013-22 pubmed publisher
    ..In summary, our data suggest that Arabidopsis csn mutants undergo DNA damage, which might be the cause of the delay in G2 cell cycle progression...