Structural highlights
Function
CUL5_HUMAN Core component of multiple SCF-like ECS (Elongin-Cullin 2/5-SOCS-box protein) E3 ubiquitin-protein ligase complexes, which mediate the ubiquitination and subsequent proteasomal degradation of target proteins. As a scaffold protein may contribute to catalysis through positioning of the substrate and the ubiquitin-conjugating enzyme. The functional specificity of the E3 ubiquitin-protein ligase complex depends on the variable substrate recognition component. ECS(SOCS1) seems to direct ubiquitination of JAk2. Seems to be involved poteosomal degradation of p53/TP53 stimulated by adenovirus E1B-55 kDa protein. May form a cell surface vasopressin receptor.
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
Cullin-RING ligases (CRLs) comprise the largest ubiquitin E3 subclass, in which a central cullin subunit links a substrate-binding adaptor with an E2-binding RING. Covalent attachment of the ubiquitin-like protein NEDD8 to a conserved C-terminal domain (ctd) lysine stimulates CRL ubiquitination activity and prevents binding of the inhibitor CAND1. Here we report striking conformational rearrangements in the crystal structure of NEDD8~Cul5(ctd)-Rbx1 and SAXS analysis of NEDD8~Cul1(ctd)-Rbx1 relative to their unmodified counterparts. In NEDD8ylated CRL structures, the cullin WHB and Rbx1 RING subdomains are dramatically reoriented, eliminating a CAND1-binding site and imparting multiple potential catalytic geometries to an associated E2. Biochemical analyses indicate that the structural malleability is important for both CRL NEDD8ylation and subsequent ubiquitination activities. Thus, our results point to a conformational control of CRL activity, with ligation of NEDD8 shifting equilibria to disfavor inactive CAND1-bound closed architectures, and favor dynamic, open forms that promote polyubiquitination.
Structural insights into NEDD8 activation of cullin-RING ligases: conformational control of conjugation.,Duda DM, Borg LA, Scott DC, Hunt HW, Hammel M, Schulman BA Cell. 2008 Sep 19;134(6):995-1006. PMID:18805092[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Duda DM, Borg LA, Scott DC, Hunt HW, Hammel M, Schulman BA. Structural insights into NEDD8 activation of cullin-RING ligases: conformational control of conjugation. Cell. 2008 Sep 19;134(6):995-1006. PMID:18805092 doi:http://dx.doi.org/10.1016/j.cell.2008.07.022
