8h3a

Structural highlights

Function

CSN5_HUMAN Probable protease subunit 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 the 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. In the complex, it probably acts as the catalytic center that mediates the cleavage of Nedd8 from cullins. It however has no metalloprotease activity by itself and requires the other subunits of the CSN complex. Interacts directly with a large number of proteins that are regulated by the CSN complex, confirming a key role in the complex. Promotes the proteasomal degradation of BRSK2.^{[1] [2] [3] [4] [5] [6] [7]}

See Also

• Ring box protein 3D structures
• Signalosome
• Ubiquitin protein ligase 3D structures

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. ↑ Cooper EM, Cutcliffe C, Kristiansen TZ, Pandey A, Pickart CM, Cohen RE. K63-specific deubiquitination by two JAMM/MPN+ complexes: BRISC-associated Brcc36 and proteasomal Poh1. EMBO J. 2009 Mar 18;28(6):621-31. doi: 10.1038/emboj.2009.27. Epub 2009 Feb 12. PMID:19214193 doi:http://dx.doi.org/10.1038/emboj.2009.27
7. ↑ Zhou J, Wan B, Li R, Gu X, Zhong Z, Wang Y, Yu L. Jab1 interacts with brain-specific kinase 2 (BRSK2) and promotes its degradation in the ubiquitin-proteasome pathway. Biochem Biophys Res Commun. 2012 Jun 15;422(4):647-52. doi:, 10.1016/j.bbrc.2012.05.045. Epub 2012 May 16. PMID:22609399 doi:http://dx.doi.org/10.1016/j.bbrc.2012.05.045