1u6g

Structural highlights

Function

[CUL1_HUMAN] Core component of multiple cullin-RING-based SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexes, which mediate the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. In the SCF complex, serves as a rigid scaffold that organizes the SKP1-F-box protein and RBX1 subunits. May contribute to catalysis through positioning of the substrate and the ubiquitin-conjugating enzyme. The E3 ubiquitin-protein ligase activity of the complex is dependent on the neddylation of the cullin subunit and is inhibited by the association of the deneddylated cullin subunit with TIP120A/CAND1. The functional specificity of the SCF complex depends on the F-box protein as substrate recognition component. SCF(BTRC) and SCF(FBXW11) direct ubiquitination of CTNNB1 and participate in Wnt signaling. SCF(FBXW11) directs ubiquitination of phosphorylated NFKBIA. SCF(BTRC) directs ubiquitination of NFKBIB, NFKBIE, ATF4, SMAD3, SMAD4, CDC25A, FBXO5 and probably NFKB2. SCF(SKP2) directs ubiquitination of phosphorylated CDKN1B/p27kip and is involved in regulation of G1/S transition. SCF(SKP2) directs ubiquitination of ORC1, CDT1, RBL2, ELF4, CDKN1A, RAG2, FOXO1A, and probably MYC and TAL1. SCF(FBXW7) directs ubiquitination of cyclin E, NOTCH1 released notch intracellular domain (NICD), and probably PSEN1. SCF(FBXW2) directs ubiquitination of GCM1. SCF(FBXO32) directs ubiquitination of MYOD1. SCF(FBXO7) directs ubiquitination of BIRC2 and DLGAP5. SCF(FBXO33) directs ubiquitination of YBX1. SCF(FBXO11) does not seem to direct ubiquitination of TP53. SCF(BTRC) mediates the ubiquitination of NFKBIA at 'Lys-21' and 'Lys-22'; the degradation frees the associated NFKB1-RELA dimer to translocate into the nucleus and to activate transcription. SCF(Cyclin F) directs ubiquitination of CP110 (By similarity).^{[1] [2] [3] [4] [5]} [CAND1_HUMAN] Enhances transcription from various types of promoters (By similarity). Regulatory protein that interferes with the assembly of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex and thereby down-regulates ubiquitination of target proteins. Prevents neddylation of CUL1 by physically blocking access to the neddylation site. Disrupts interactions between CUL1 and SKP1 and between CUL1 and F-box proteins.^{[6] [7] [8]} [RBX1_HUMAN] E3 ubiquitin ligase component of multiple cullin-RING-based E3 ubiquitin-protein ligase complexes which mediate the ubiquitination and subsequent proteasomal degradation of target proteins, including proteins involved in cell cycle progression, signal transduction, transcription and transcription-coupled nucleotide excision repair. The functional specificity of the E3 ubiquitin-protein ligase complexes depends on the variable substrate recognition components. As a component of the CSA complex promotes the ubiquitination of ERCC6 resulting in proteasomal degradation. Through the RING-type zinc finger, seems to recruit the E2 ubiquitination enzyme, like CDC34, to the complex and brings it into close proximity to the substrate. Probably also stimulates CDC34 autoubiquitination. May be required for histone H3 and histone H4 ubiquitination in response to ultraviolet and for subsequent DNA repair. Promotes the neddylation of CUL1, CUL2, CUL4 and CUL4 via its interaction with UBE2M.^{[9] [10] [11] [12] [13]}

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

References

1. ↑ Michel JJ, Xiong Y. Human CUL-1, but not other cullin family members, selectively interacts with SKP1 to form a complex with SKP2 and cyclin A. Cell Growth Differ. 1998 Jun;9(6):435-49. PMID:9663463
2. ↑ Tintignac LA, Lagirand J, Batonnet S, Sirri V, Leibovitch MP, Leibovitch SA. Degradation of MyoD mediated by the SCF (MAFbx) ubiquitin ligase. J Biol Chem. 2005 Jan 28;280(4):2847-56. Epub 2004 Nov 5. PMID:15531760 doi:M411346200
3. ↑ Yang CS, Yu C, Chuang HC, Chang CW, Chang GD, Yao TP, Chen H. FBW2 targets GCMa to the ubiquitin-proteasome degradation system. J Biol Chem. 2005 Mar 18;280(11):10083-90. Epub 2005 Jan 8. PMID:15640526 doi:M413986200
4. ↑ Lovly CM, Yan L, Ryan CE, Takada S, Piwnica-Worms H. Regulation of Chk2 ubiquitination and signaling through autophosphorylation of serine 379. Mol Cell Biol. 2008 Oct;28(19):5874-85. doi: 10.1128/MCB.00821-08. Epub 2008 Jul , 21. PMID:18644861 doi:10.1128/MCB.00821-08
5. ↑ Isobe T, Hattori T, Kitagawa K, Uchida C, Kotake Y, Kosugi I, Oda T, Kitagawa M. Adenovirus E1A inhibits SCF(Fbw7) ubiquitin ligase. J Biol Chem. 2009 Oct 9;284(41):27766-79. Epub 2009 Aug 13. PMID:19679664 doi:M109.006809
6. ↑ Zheng J, Yang X, Harrell JM, Ryzhikov S, Shim EH, Lykke-Andersen K, Wei N, Sun H, Kobayashi R, Zhang H. CAND1 binds to unneddylated CUL1 and regulates the formation of SCF ubiquitin E3 ligase complex. Mol Cell. 2002 Dec;10(6):1519-26. PMID:12504026
7. ↑ Liu J, Furukawa M, Matsumoto T, Xiong Y. NEDD8 modification of CUL1 dissociates p120(CAND1), an inhibitor of CUL1-SKP1 binding and SCF ligases. Mol Cell. 2002 Dec;10(6):1511-8. PMID:12504025
8. ↑ Min KW, Hwang JW, Lee JS, Park Y, Tamura TA, Yoon JB. TIP120A associates with cullins and modulates ubiquitin ligase activity. J Biol Chem. 2003 May 2;278(18):15905-10. Epub 2003 Feb 27. PMID:12609982 doi:10.1074/jbc.M213070200
9. ↑ Kamura T, Conrad MN, Yan Q, Conaway RC, Conaway JW. The Rbx1 subunit of SCF and VHL E3 ubiquitin ligase activates Rub1 modification of cullins Cdc53 and Cul2. Genes Dev. 1999 Nov 15;13(22):2928-33. PMID:10579999
10. ↑ Furukawa M, Zhang Y, McCarville J, Ohta T, Xiong Y. The CUL1 C-terminal sequence and ROC1 are required for efficient nuclear accumulation, NEDD8 modification, and ubiquitin ligase activity of CUL1. Mol Cell Biol. 2000 Nov;20(21):8185-97. PMID:11027288
11. ↑ Groisman R, Kuraoka I, Chevallier O, Gaye N, Magnaldo T, Tanaka K, Kisselev AF, Harel-Bellan A, Nakatani Y. CSA-dependent degradation of CSB by the ubiquitin-proteasome pathway establishes a link between complementation factors of the Cockayne syndrome. Genes Dev. 2006 Jun 1;20(11):1429-34. PMID:16751180 doi:http://dx.doi.org/10.1101/gad.378206
12. ↑ Wang H, Zhai L, Xu J, Joo HY, Jackson S, Erdjument-Bromage H, Tempst P, Xiong Y, Zhang Y. Histone H3 and H4 ubiquitylation by the CUL4-DDB-ROC1 ubiquitin ligase facilitates cellular response to DNA damage. Mol Cell. 2006 May 5;22(3):383-94. PMID:16678110 doi:S1097-2765(06)00230-9
13. ↑ Isobe T, Hattori T, Kitagawa K, Uchida C, Kotake Y, Kosugi I, Oda T, Kitagawa M. Adenovirus E1A inhibits SCF(Fbw7) ubiquitin ligase. J Biol Chem. 2009 Oct 9;284(41):27766-79. Epub 2009 Aug 13. PMID:19679664 doi:M109.006809
14. ↑ Goldenberg SJ, Cascio TC, Shumway SD, Garbutt KC, Liu J, Xiong Y, Zheng N. Structure of the Cand1-Cul1-Roc1 complex reveals regulatory mechanisms for the assembly of the multisubunit cullin-dependent ubiquitin ligases. Cell. 2004 Nov 12;119(4):517-28. PMID:15537541 doi:10.1016/j.cell.2004.10.019