2lxh

NMR structure of the RING domain in ubiquitin ligase gp78NMR structure of the RING domain in ubiquitin ligase gp78

Structural highlights

2lxh is a 1 chain structure with sequence from Homo sapiens. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Solution NMR
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

AMFR_HUMAN E3 ubiquitin-protein ligase that mediates the polyubiquitination of a number of proteins such as CD3D, CYP3A4, CFTR and APOB for proteasomal degradation. Component of a VCP/p97-AMFR/gp78 complex that participates in the final step of endoplasmic reticulum-associated degradation (ERAD). The VCP/p97-AMFR/gp78 complex is involved in the sterol-accelerated ERAD degradation of HMGCR through binding to the HMGCR-INSIG complex at the ER membrane and initiating ubiquitination of HMGCR. The ubiquitinated HMGCR is then released from the ER by the complex into the cytosol for subsequent destruction. Also acts as a scaffold protein to assemble a complex that couples ubiquitination, retranslocation and deglycosylation. Mediates tumor invasion and metastasis as a receptor for the GPI/autocrine motility factor.^[1] ^[2] ^[3] ^[4]

Publication Abstract from PubMed

RING finger proteins constitute the large majority of ubiquitin ligases (E3s) and function by interacting with ubiquitin-conjugating enzymes (E2s) charged with ubiquitin. How low-affinity RING-E2 interactions result in highly processive substrate ubiquitination is largely unknown. The RING E3, gp78, represents an excellent model to study this process. gp78 includes a high-affinity secondary binding region for its cognate E2, Ube2g2, the G2BR. The G2BR allosterically enhances RING:Ube2g2 binding and ubiquitination. Structural analysis of the RING:Ube2g2:G2BR complex reveals that a G2BR-induced conformational effect at the RING:Ube2g2 interface is necessary for enhanced binding of RING to Ube2g2 or Ube2g2 conjugated to Ub. This conformational effect and a key ternary interaction with conjugated ubiquitin are required for ubiquitin transfer. Moreover, RING:Ube2g2 binding induces a second allosteric effect, disrupting Ube2g2:G2BR contacts, decreasing affinity and facilitating E2 exchange. Thus, gp78 is a ubiquitination machine where multiple E2-binding sites coordinately facilitate processive ubiquitination.

Allosteric regulation of E2:E3 interactions promote a processive ubiquitination machine.,Das R, Liang YH, Mariano J, Li J, Huang T, King A, Tarasov SG, Weissman AM, Ji X, Byrd RA EMBO J. 2013 Aug 13. doi: 10.1038/emboj.2013.174. PMID:23942235^[5]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Shimizu K, Tani M, Watanabe H, Nagamachi Y, Niinaka Y, Shiroishi T, Ohwada S, Raz A, Yokota J. The autocrine motility factor receptor gene encodes a novel type of seven transmembrane protein. FEBS Lett. 1999 Aug 6;456(2):295-300. PMID:10456327
↑ Fang S, Ferrone M, Yang C, Jensen JP, Tiwari S, Weissman AM. The tumor autocrine motility factor receptor, gp78, is a ubiquitin protein ligase implicated in degradation from the endoplasmic reticulum. Proc Natl Acad Sci U S A. 2001 Dec 4;98(25):14422-7. Epub 2001 Nov 27. PMID:11724934 doi:10.1073/pnas.251401598
↑ Song BL, Sever N, DeBose-Boyd RA. Gp78, a membrane-anchored ubiquitin ligase, associates with Insig-1 and couples sterol-regulated ubiquitination to degradation of HMG CoA reductase. Mol Cell. 2005 Sep 16;19(6):829-40. PMID:16168377 doi:10.1016/j.molcel.2005.08.009
↑ Pabarcus MK, Hoe N, Sadeghi S, Patterson C, Wiertz E, Correia MA. CYP3A4 ubiquitination by gp78 (the tumor autocrine motility factor receptor, AMFR) and CHIP E3 ligases. Arch Biochem Biophys. 2009 Mar 1;483(1):66-74. doi: 10.1016/j.abb.2008.12.001., Epub 2008 Dec 10. PMID:19103148 doi:10.1016/j.abb.2008.12.001
↑ Das R, Liang YH, Mariano J, Li J, Huang T, King A, Tarasov SG, Weissman AM, Ji X, Byrd RA. Allosteric regulation of E2:E3 interactions promote a processive ubiquitination machine. EMBO J. 2013 Aug 13. doi: 10.1038/emboj.2013.174. PMID:23942235 doi:10.1038/emboj.2013.174

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

[1] Shimizu K, Tani M, Watanabe H, Nagamachi Y, Niinaka Y, Shiroishi T, Ohwada S, Raz A, Yokota J. The autocrine motility factor receptor gene encodes a novel type of seven transmembrane protein. FEBS Lett. 1999 Aug 6;456(2):295-300. PMID:10456327

[2] Fang S, Ferrone M, Yang C, Jensen JP, Tiwari S, Weissman AM. The tumor autocrine motility factor receptor, gp78, is a ubiquitin protein ligase implicated in degradation from the endoplasmic reticulum. Proc Natl Acad Sci U S A. 2001 Dec 4;98(25):14422-7. Epub 2001 Nov 27. PMID:11724934 doi:10.1073/pnas.251401598

[3] Song BL, Sever N, DeBose-Boyd RA. Gp78, a membrane-anchored ubiquitin ligase, associates with Insig-1 and couples sterol-regulated ubiquitination to degradation of HMG CoA reductase. Mol Cell. 2005 Sep 16;19(6):829-40. PMID:16168377 doi:10.1016/j.molcel.2005.08.009

[4] Pabarcus MK, Hoe N, Sadeghi S, Patterson C, Wiertz E, Correia MA. CYP3A4 ubiquitination by gp78 (the tumor autocrine motility factor receptor, AMFR) and CHIP E3 ligases. Arch Biochem Biophys. 2009 Mar 1;483(1):66-74. doi: 10.1016/j.abb.2008.12.001., Epub 2008 Dec 10. PMID:19103148 doi:10.1016/j.abb.2008.12.001

[5] Das R, Liang YH, Mariano J, Li J, Huang T, King A, Tarasov SG, Weissman AM, Ji X, Byrd RA. Allosteric regulation of E2:E3 interactions promote a processive ubiquitination machine. EMBO J. 2013 Aug 13. doi: 10.1038/emboj.2013.174. PMID:23942235 doi:10.1038/emboj.2013.174

[1]

[2]

[3]

[4]

[5]