3ZNI

Structure of phosphoTyr363-Cbl-b - UbcH5B-Ub - ZAP-70 peptide complex

Summary for 3ZNI

• Entry DOI: 10.2210/pdb3zni/pdb
• Descriptor: E3 UBIQUITIN-PROTEIN LIGASE CBL-B, TYROSINE-PROTEIN KINASE ZAP-70, UBIQUITIN-CONJUGATING ENZYME E2 D2, ... (8 entities in total)
• Functional Keywords: ligase, ligases, degradation
• Biological source: HOMO SAPIENS (HUMAN); More
• Total number of polymer chains: 16
• Total formula weight: 291871.39

Authors

Dou, H.,Buetow, L.,Sibbet, G.J.,Cameron, K.,Huang, D.T. (deposition date: 2013-02-14, release date: 2013-07-10, Last modification date: 2024-11-06)

Primary citation

Dou, H.,Buetow, L.,Sibbet, G.J.,Cameron, K.,Huang, D.T.
Essentiality of a Non-Ring Element in Priming Donor Ubiquitin for Catalysis by a Monomeric E3.
Nat.Struct.Mol.Biol., 20:982-, 2013

PubMed Abstract: RING E3 ligases catalyze the transfer of ubiquitin (Ub) from E2 ubiquitin-conjugating enzyme thioesterified with Ub (E2~Ub) to substrate. For RING E3 dimers, the RING domain of one subunit and tail of the second cooperate to prime Ub, but how this is accomplished by monomeric RING E3s in the absence of a tail-like component is currently unknown. Here, we present a crystal structure of a monomeric RING E3, Tyr363-phosphorylated human CBL-B, bound to a stabilized Ub-linked E2, revealing a similar mechanism in activating E2~Ub. Both pTyr363 and the pTyr363-induced element interact directly with Ub's Ile36 surface, improving the catalytic efficiency of Ub transfer by ~200-fold. Hence, interactions outside the canonical RING domain are crucial for optimizing Ub transfer in both monomeric and dimeric RING E3s. We propose that an additional non-RING Ub-priming element may be a common RING E3 feature.

PubMed: 23851457
DOI: 10.1038/NSMB.2621

Experimental method

X-RAY DIFFRACTION (2.21 Å)