4qft

Structural highlights

Function

[CSN6_HUMAN] Component of the COP9 signalosome complex (CSN), a complex involved in various cellular and developmental processes. The CSN complex is an essential regulator of the ubiquitin (Ubl) conjugation pathway by mediating the deneddylation of the cullin subunits of SCF-type E3 ligase complexes, leading to decrease the Ubl ligase activity of SCF-type complexes such as SCF, CSA or DDB2. The complex is also involved in phosphorylation of p53/TP53, c-jun/JUN, IkappaBalpha/NFKBIA, ITPK1 and IRF8, possibly via its association with CK2 and PKD kinases. CSN-dependent phosphorylation of TP53 and JUN promotes and protects degradation by the Ubl system, respectively. Has some glucocorticoid receptor-responsive activity. Stabilizes RFWD2/COP1 through reducing RFWD2 auto-ubiquitination and decelerating RFWD2 turnover rate, hence regulates the ubiquitination of RFWD2 targets.^{[1] [2] [3] [4] [5] [6]}

See Also

• Signalosome

References

1. ↑ Seeger M, Kraft R, Ferrell K, Bech-Otschir D, Dumdey R, Schade R, Gordon C, Naumann M, Dubiel W. A novel protein complex involved in signal transduction possessing similarities to 26S proteasome subunits. FASEB J. 1998 Apr;12(6):469-78. PMID:9535219
2. ↑ Bech-Otschir D, Kraft R, Huang X, Henklein P, Kapelari B, Pollmann C, Dubiel W. COP9 signalosome-specific phosphorylation targets p53 to degradation by the ubiquitin system. EMBO J. 2001 Apr 2;20(7):1630-9. PMID:11285227 doi:http://dx.doi.org/10.1093/emboj/20.7.1630
3. ↑ Lyapina S, Cope G, Shevchenko A, Serino G, Tsuge T, Zhou C, Wolf DA, Wei N, Shevchenko A, Deshaies RJ. Promotion of NEDD-CUL1 conjugate cleavage by COP9 signalosome. Science. 2001 May 18;292(5520):1382-5. Epub 2001 May 3. PMID:11337588 doi:http://dx.doi.org/10.1126/science.1059780
4. ↑ Groisman R, Polanowska J, Kuraoka I, Sawada J, Saijo M, Drapkin R, Kisselev AF, Tanaka K, Nakatani Y. The ubiquitin ligase activity in the DDB2 and CSA complexes is differentially regulated by the COP9 signalosome in response to DNA damage. Cell. 2003 May 2;113(3):357-67. PMID:12732143
5. ↑ Uhle S, Medalia O, Waldron R, Dumdey R, Henklein P, Bech-Otschir D, Huang X, Berse M, Sperling J, Schade R, Dubiel W. Protein kinase CK2 and protein kinase D are associated with the COP9 signalosome. EMBO J. 2003 Mar 17;22(6):1302-12. PMID:12628923 doi:http://dx.doi.org/10.1093/emboj/cdg127
6. ↑ Choi HH, Gully C, Su CH, Velazquez-Torres G, Chou PC, Tseng C, Zhao R, Phan L, Shaiken T, Chen J, Yeung SC, Lee MH. COP9 signalosome subunit 6 stabilizes COP1, which functions as an E3 ubiquitin ligase for 14-3-3sigma. Oncogene. 2011 Dec 1;30(48):4791-801. doi: 10.1038/onc.2011.192. Epub 2011 May, 30. PMID:21625211 doi:http://dx.doi.org/10.1038/onc.2011.192