| Structural highlights
4eb9 is a 4 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , |
| Related: | 3mup, 3oz1, 4ec4 |
| Gene: | BIRC2, API1, IAP2, MIHB, RNF48 (Homo sapiens) |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
Function
[BIRC2_HUMAN] Multi-functional protein which regulates not only caspases and apoptosis, but also modulates inflammatory signaling and immunity, mitogenic kinase signaling, and cell proliferation, as well as cell invasion and metastasis. Acts as an E3 ubiquitin-protein ligase regulating NF-kappa-B signaling and regulates both canonical and non-canonical NF-kappa-B signaling by acting in opposite directions: acts as a positive regulator of the canonical pathway and suppresses constitutive activation of non-canonical NF-kappa-B signaling. The target proteins for its E3 ubiquitin-protein ligase activity include: RIPK1, RIPK2, RIPK3, RIPK4, CASP3, CASP7, CASP8, TRAF2, DIABLO/SMAC, MAP3K14/NIK, MAP3K5/ASK1, IKBKG/NEMO and MXD1/MAD1. Can also function as an E3 ubiquitin-protein ligase of the NEDD8 conjugation pathway, targeting effector caspases for neddylation and inactivation. Acts as an important regulator of innate immune signaling via regulation of Toll-like receptors (TLRs), Nodlike receptors (NLRs) and RIG-I like receptors (RLRs), collectively referred to as pattern recognition receptors (PRRs). Protects cells from spontaneous formation of the ripoptosome, a large multi-protein complex that has the capability to kill cancer cells in a caspase-dependent and caspase-independent manner. Suppresses ripoptosome formation by ubiquitinating RIPK1 and CASP8. Can stimulate the transcriptional activity of E2F1. Plays a role in the modulation of the cell cycle.[1] [2] [3] [4] [5]
Publication Abstract from PubMed
Genetic alterations enhancing cell survival and suppressing apoptosis are hallmarks of cancer that significantly reduce the efficacy of chemotherapy or radiotherapy. The Inhibitor of Apoptosis Protein (IAP) family hosts conserved proteins in the apoptotic pathway whose over-expression, frequently found in tumours, potentiates survival and resistance to anticancer agents. In humans, IAPs comprise eight members hosting one or more structural Baculoviral IAP Repeat (BIR) domains. Cellular IAPs (cIAP1 and 2) indirectly inhibit caspase-8 activation, and regulate both the canonical and the non-canonical NF-kappaB signaling pathways. In contrast to cIAPs, XIAP (X chromosome-linked Inhibitor of Apoptosis Protein) inhibits directly the effector caspases-3 and -7 through its BIR2 domain, and initiator caspase-9 through its BIR3 domain; molecular docking studies suggested that Smac/DIABLO antagonizes XIAP by simultaneously targeting both BIR2 and BIR3 domains. Here we report analytical gel filtration, crystallographic and SAXS experiments on cIAP1-BIR3, XIAP-BIR3 and XIAP-BIR2BIR3 domains, alone and in the presence of compound 9a, a divalent homodimeric Smac mimetic. 9a is shown to bind two BIR domains inter- (in the case of two BIR3) and intra-molecularly (in the case of XIAP-BIR2BIR3), with higher affinity for cIAP1-BIR3, relative to XIAP-BIR3. Despite the different crystal lattice packing, 9a maintains a right handed helical conformation in both cIAP1-BIR3 and XIAP-BIR3 crystals, that is likely conserved in solution as shown by SAXS data. Our structural results demonstrate that the 9a linker length, its conformational degrees of freedom and its hydrophobicity, warrant an overall compact structure with optimal solvent exposure of its two active moieties for IAPs binding. Our results show that 9a is a good candidate for pre-clinical and clinical studies, worth of further investigations in the field of cancer therapy.
Structural insight into inhibitor of apoptosis proteins recognition by a potent divalent smac-mimetic.,Cossu F, Milani M, Vachette P, Malvezzi F, Grassi S, Lecis D, Delia D, Drago C, Seneci P, Bolognesi M, Mastrangelo E PLoS One. 2012;7(11):e49527. doi: 10.1371/journal.pone.0049527. Epub 2012 Nov 15. PMID:23166698[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Samuel T, Okada K, Hyer M, Welsh K, Zapata JM, Reed JC. cIAP1 Localizes to the nuclear compartment and modulates the cell cycle. Cancer Res. 2005 Jan 1;65(1):210-8. PMID:15665297
- ↑ Xu L, Zhu J, Hu X, Zhu H, Kim HT, LaBaer J, Goldberg A, Yuan J. c-IAP1 cooperates with Myc by acting as a ubiquitin ligase for Mad1. Mol Cell. 2007 Dec 14;28(5):914-22. PMID:18082613 doi:10.1016/j.molcel.2007.10.027
- ↑ Broemer M, Tenev T, Rigbolt KT, Hempel S, Blagoev B, Silke J, Ditzel M, Meier P. Systematic in vivo RNAi analysis identifies IAPs as NEDD8-E3 ligases. Mol Cell. 2010 Dec 10;40(5):810-22. doi: 10.1016/j.molcel.2010.11.011. PMID:21145488 doi:10.1016/j.molcel.2010.11.011
- ↑ Cartier J, Berthelet J, Marivin A, Gemble S, Edmond V, Plenchette S, Lagrange B, Hammann A, Dupoux A, Delva L, Eymin B, Solary E, Dubrez L. Cellular inhibitor of apoptosis protein-1 (cIAP1) can regulate E2F1 transcription factor-mediated control of cyclin transcription. J Biol Chem. 2011 Jul 29;286(30):26406-17. doi: 10.1074/jbc.M110.191239. Epub, 2011 Jun 8. PMID:21653699 doi:10.1074/jbc.M110.191239
- ↑ Bertrand MJ, Lippens S, Staes A, Gilbert B, Roelandt R, De Medts J, Gevaert K, Declercq W, Vandenabeele P. cIAP1/2 are direct E3 ligases conjugating diverse types of ubiquitin chains to receptor interacting proteins kinases 1 to 4 (RIP1-4). PLoS One. 2011;6(9):e22356. doi: 10.1371/journal.pone.0022356. Epub 2011 Sep 12. PMID:21931591 doi:10.1371/journal.pone.0022356
- ↑ Cossu F, Milani M, Vachette P, Malvezzi F, Grassi S, Lecis D, Delia D, Drago C, Seneci P, Bolognesi M, Mastrangelo E. Structural insight into inhibitor of apoptosis proteins recognition by a potent divalent smac-mimetic. PLoS One. 2012;7(11):e49527. doi: 10.1371/journal.pone.0049527. Epub 2012 Nov 15. PMID:23166698 doi:http://dx.doi.org/10.1371/journal.pone.0049527
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