My lab is focused on understanding the role of the COP9 signalosome (CSN) and eIF3 in regulating development. The CSN is a multi-subunit protein complex that was originally identified in Arabidopsis (Chamovitz et al., 1996), but which we later showed to be essential for animal development (Freilich et al., 1999; Oron et al., 2002). The CSN functions at the nexus of signaling inputs and ubiquitin-mediated protein degradation pathways. Our recent data also implicates the CSN in translational control through its interaction with eIF3 (Yahalom et al., 2001, 2008). We are using a combination of genetic, biochemical, molecular and genomic approaches to dissect the varied roles of the CSN in the development of plants and animals, using both Arabidopsis and Drosophila as model systems. Our results implicate roles for the CSN in multiple processes including kinase signaling, translational regulation, and cellular differentiation.

Specific topics:

• Systems biology approaches to studying the CSN and eIF3 and their developmental function.
• Bioinformatic approaches for cross-organismic transcripome analysis
• Revealing the interaction of the COP9 signalosome and eIF3 in Arabidopsis development.
• Elucidating the roles of specific CSN subunits by:
  • Structure/function of CSN subunit 7 and its multiple interacting proteins.
  • Studying Drosophila mutants in each CSN subunit.
  • Large-scale microarray analysis of csn mutants
• Elucidating the roles of eIF3 subunit "e" in translational regulation and Arabidopsis development
• The role of an anti-cancer drug in plants

For more information, please go to the Chamovitz Lab Home Page

Systems Biology

1. Atias, D, Chor, B, and Chamovitz, DA (2009) Large-scale analysis of Arabidopsis transcription reveals a basal co-regulation network. BMC Systems Biology 3:86
2. Oron E, Tuller, T, Li, L, Yekutieli, D, Rencus-Lazar, S, Segal, D, Chor, B, Edgar, BA and Chamovitz, DA (2007) Genomic analysis of COP9 signalosome function in Drosophila melanogaster reveals a role in temporal regulation of gene expression. Molecular Systems Biology 3:108.
3. Tuller, T. et al. (2005) Time-Window Analysis of Developmental Gene Expression Data with Multiple Genetic Backgrounds. Algorithms in Bioinformatics, R. Casadio, and G. Myers, eds. Berlin, Springer Verlag, 2005 (pp. 53-64).
4. Chamovitz DA and Yahalom A. (2003) A systems approach to the COP9 signalosome. Plant Physiol. 132.

Drosophila CSN

1. Oron E, Tuller, T, Li, L, Yekutieli, D, Rencus-Lazar, S, Segal, D, Chor, B, Edgar, BA and Chamovitz, DA (2007) Genomic analysis of COP9 signalosome function in Drosophila melanogaster reveals a role in temporal regulation of gene expression. Molecular Systems Biology 3:108.
2. Harari-Steinberg, O., Cantera, R., Denti, S., Bianchi, E., Oron, E., Segal, D., and Chamovitz, D.A. (2007) COP9 signalosome subunit 5 (CSN5/JAB1) regulates the development of the Drosophila immune system: effect on Cactus, Dorsal amd hematopiesis. Genes to Cells 12: 183-195.
3. Oron E, Mannervik M, Rencus S, Harari-Steinberg O, Neuman-Silberberg S, Segal D, Chamovitz DA. (2002). COP9 signalosome subunits 4 and 5 regulate multiple pleiotropic pathways in Drosophila melanogaster. Development 129: 4399-409.
4. Freilich S, Oron E, Kapp Y, Nevo-Caspi Y, Orgad S, Segal D, Chamovitz DA. (1999) The COP9 signalosome is essential for development of Drosophila melanogaster. Curr Biol. 9: 1187-9.

Arabidopsis CSN and eIF3

1. Dessau, M., Halimi, Y., Erez, T., Chomsky-Hecht, O., Chamovitz, DA  Hirsch, JA (2008) The Arabidopsis COP9 Signalsome subunit 7 is a model PCI domain protein with subdomains involved in COP9 Signalsome assembly. Plant Cell 20, 2815-2834.
2. Yahalom A, Kim TH, Roy, B, Singer, R, von Arnim AG, Chamovitz DA. (2008). Arabidopsis eIF3e is regulated by the COP9 signalosome and has an impact on development and protein translation. Plant J. 53, 300-311.
3. Yahalom A, Kim TH, Winter E, Karniol B, von Arnim AG, Chamovitz DA. (2001). Arabidopsis eIF3e (INT-6) associates with both eIF3c and the COP9 signalosome subunit CSN7. J. Biol Chem. 276, 334-40.
4. Karniol B, Malec P, Chamovitz DA. (1999) Arabidopsis FUSCA5 encodes a novel phosphoprotein that is a component of the COP9 complex. Plant Cell 11: 839-48.
5. Chamovitz, DA, Wei, N, Osterlund, MT, von Arnim, A., Matsui, M, and Deng, XW. (1996) The COP9 complex, a novel multisubunit nuclear regulator involved in light control of a plant developmental switch. Cell 86, 115-21.

Reviews

1. Chamovitz DA (2009) Revisiting the COP9 signalosome as a transcriptional regulator. EMBO Rep 10, 352-358.
2. Harari-Steinberg, O., and Chamovitz D.A. (2004) The COP9 signalosome: mediating between kinase signaling and protein degradation Curr Protein Pept Sci
3. von Arnim AG and Chamovitz DA. (2003) Protein Homeostasis: A Degrading Role for Int6/eIF3e. Curr Biol. 13: R323-5.
4. Deng XW, Dubiel W, Wei N, Hofmann K, Mundt K, Colicelli J, Kato J, Naumann M, Segal D, Seeger M, Carr A, Glickman M, Chamovitz DA. (2000) Unified nomenclature for the COP9 signalosome and its subunits: an essential regulator of development. Trends Genet.16: 202-3.

 For all Chamovitz lab publications, with links to the papers, click here. My full list of publications can be found here.