| Structural highlights
Disease
[CBL_HUMAN] Defects in CBL are the cause of Noonan syndrome-like disorder with or without juvenile myelomonocytic leukemia (NSLL) [MIM:613563]. A syndrome characterized by a phenotype reminiscent of Noonan syndrome. Clinical features are highly variable, including facial dysmorphism, short neck, developmental delay, hyperextensible joints and thorax abnormalities with widely spaced nipples. The facial features consist of triangular face with hypertelorism, large low-set ears, ptosis, and flat nasal bridge. Some patients manifest cardiac defects.[1]
Function
[CBL_HUMAN] Adapter protein that functions as a negative regulator of many signaling pathways that are triggered by activation of cell surface receptors. Acts as an E3 ubiquitin-protein ligase, which accepts ubiquitin from specific E2 ubiquitin-conjugating enzymes, and then transfers it to substrates promoting their degradation by the proteasome. Recognizes activated receptor tyrosine kinases, including KIT, FLT1, FGFR1, FGFR2, PDGFRA, PDGFRB, EGFR, CSF1R, EPHA8 and KDR and terminates signaling. Recognizes membrane-bound HCK and other kinases of the SRC family and mediates their ubiquitination and degradation. Participates in signal transduction in hematopoietic cells. Plays an important role in the regulation of osteoblast differentiation and apoptosis. Essential for osteoclastic bone resorption. The Tyr-731 phosphorylated form induces the activation and recruitment of phosphatidylinositol 3-kinase to the cell membrane in a signaling pathway that is critical for osteoclast function.[2] [3] [4] [5] [6] [7] [8] [9]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The Cbl proteins, RING-type E3 ubiquitin ligases, are responsible for ubiquitinating the activated tyrosine kinases and targeting them for degradation. Both c-Cbl and Cbl-b have a UBA (ubiquitin-associated) domain at their C-terminal ends, and these two UBA domains share a high sequence similarity (75%). However, only the UBA from Cbl-b, but not from c-Cbl, can bind ubiquitin (Ub). To understand the mechanism by which the UBA domains specifically interact with Ub with different affinities, we determined the solution NMR structures of these two UBA domains, cUBA from human c-Cbl and UBAb from Cbl-b. Their structures show that these two UBA domains share the same fold, a compact three-helix bundle, highly resembling the typical UBA fold. Chemical shift perturbation experiments reveal that the helix-1 and loop-1 of UBAb form a predominately hydrophobic surface for Ub binding. By comparing the Ub-interacting surface on UBAb and its counterpart on cUBA, we find that the hydrophobic patch on cUBA is interrupted by a negatively charged residue Glu12. Fluorescence titration data show that the Ala12Glu mutant of UBAb completely loses the ability to bind Ub, whereas the mutation disrupting the dimerization has no significant effect on Ub binding. This study provides structural and biochemical insights into the Ub binding specificities of the Cbl UBA domains, in which the hydrophobic surface distribution on the first helix plays crucial roles in their differential affinities for Ub binding. That is, the amino acid residue diversity in the helix-1 region, but not the dimerization, determines the abilities of various UBA domains binding with Ub.
Differential ubiquitin binding of the UBA domains from human c-Cbl and Cbl-b: NMR structural and biochemical insights.,Zhou ZR, Gao HC, Zhou CJ, Chang YG, Hong J, Song AX, Lin DH, Hu HY Protein Sci. 2008 Oct;17(10):1805-14. Epub 2008 Jul 2. PMID:18596201[10]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Martinelli S, De Luca A, Stellacci E, Rossi C, Checquolo S, Lepri F, Caputo V, Silvano M, Buscherini F, Consoli F, Ferrara G, Digilio MC, Cavaliere ML, van Hagen JM, Zampino G, van der Burgt I, Ferrero GB, Mazzanti L, Screpanti I, Yntema HG, Nillesen WM, Savarirayan R, Zenker M, Dallapiccola B, Gelb BD, Tartaglia M. Heterozygous germline mutations in the CBL tumor-suppressor gene cause a Noonan syndrome-like phenotype. Am J Hum Genet. 2010 Aug 13;87(2):250-7. doi: 10.1016/j.ajhg.2010.06.015. Epub, 2010 Jul 8. PMID:20619386 doi:10.1016/j.ajhg.2010.06.015
- ↑ Joazeiro CA, Wing SS, Huang H, Leverson JD, Hunter T, Liu YC. The tyrosine kinase negative regulator c-Cbl as a RING-type, E2-dependent ubiquitin-protein ligase. Science. 1999 Oct 8;286(5438):309-12. PMID:10514377
- ↑ Howlett CJ, Robbins SM. Membrane-anchored Cbl suppresses Hck protein-tyrosine kinase mediated cellular transformation. Oncogene. 2002 Mar 7;21(11):1707-16. PMID:11896602 doi:10.1038/sj.onc.1205228
- ↑ Miyazaki T, Sanjay A, Neff L, Tanaka S, Horne WC, Baron R. Src kinase activity is essential for osteoclast function. J Biol Chem. 2004 Apr 23;279(17):17660-6. Epub 2004 Jan 22. PMID:14739300 doi:10.1074/jbc.M311032200
- ↑ Kaabeche K, Lemonnier J, Le Mee S, Caverzasio J, Marie PJ. Cbl-mediated degradation of Lyn and Fyn induced by constitutive fibroblast growth factor receptor-2 activation supports osteoblast differentiation. J Biol Chem. 2004 Aug 27;279(35):36259-67. Epub 2004 Jun 9. PMID:15190072 doi:10.1074/jbc.M402469200
- ↑ Bonaventure J, Horne WC, Baron R. The localization of FGFR3 mutations causing thanatophoric dysplasia type I differentially affects phosphorylation, processing and ubiquitylation of the receptor. FEBS J. 2007 Jun;274(12):3078-93. Epub 2007 May 17. PMID:17509076 doi:10.1111/j.1742-4658.2007.05835.x
- ↑ Dufour C, Guenou H, Kaabeche K, Bouvard D, Sanjay A, Marie PJ. FGFR2-Cbl interaction in lipid rafts triggers attenuation of PI3K/Akt signaling and osteoblast survival. Bone. 2008 Jun;42(6):1032-9. doi: 10.1016/j.bone.2008.02.009. Epub 2008 Feb 29. PMID:18374639 doi:10.1016/j.bone.2008.02.009
- ↑ Wehrle C, Van Slyke P, Dumont DJ. Angiopoietin-1-induced ubiquitylation of Tie2 by c-Cbl is required for internalization and degradation. Biochem J. 2009 Oct 12;423(3):375-80. doi: 10.1042/BJ20091010. PMID:19689429 doi:10.1042/BJ20091010
- ↑ Severe N, Miraoui H, Marie PJ. The Casitas B lineage lymphoma (Cbl) mutant G306E enhances osteogenic differentiation in human mesenchymal stromal cells in part by decreased Cbl-mediated platelet-derived growth factor receptor alpha and fibroblast growth factor receptor 2 ubiquitination. J Biol Chem. 2011 Jul 8;286(27):24443-50. doi: 10.1074/jbc.M110.197525. Epub 2011, May 19. PMID:21596750 doi:10.1074/jbc.M110.197525
- ↑ Zhou ZR, Gao HC, Zhou CJ, Chang YG, Hong J, Song AX, Lin DH, Hu HY. Differential ubiquitin binding of the UBA domains from human c-Cbl and Cbl-b: NMR structural and biochemical insights. Protein Sci. 2008 Oct;17(10):1805-14. Epub 2008 Jul 2. PMID:18596201 doi:10.1110/ps.036384.108
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