6OI4

RPN13 (19-132)-RPN2 (940-952) pY950-Ub complex

Summary for 6OI4

• Entry DOI: 10.2210/pdb6oi4/pdb
• Descriptor: Proteasomal ubiquitin receptor ADRM1, ubiquitin, 26S proteasome non-ATPase regulatory subunit 1, ... (5 entities in total)
• Functional Keywords: pru, proteasome, ubiquitin, protein binding
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 6
• Total formula weight: 47842.11

Authors

Hemmis, C.W.,Hill, C.P. (deposition date: 2019-04-08, release date: 2019-05-15, Last modification date: 2024-10-23)

Primary citation

Hemmis, C.W.,Heard, S.C.,Hill, C.P.
Phosphorylation of Tyr-950 in the proteasome scaffolding protein RPN2 modulates its interaction with the ubiquitin receptor RPN13.
J.Biol.Chem., 294:9659-9665, 2019

PubMed Abstract: Protein substrates are targeted to the 26S proteasome through several ubiquitin receptors. One of these receptors, RPN13, is recruited to the proteasome by binding of its N-terminal pleckstrin-like receptor of ubiquitin (PRU) domain to C-terminal residues of the scaffolding protein RPN2. The RPN13 PRU domain is followed by a flexible linker and a C-terminal deubiquitylase adaptor (DEUBAD) domain, which recruits and activates the deubiquitylase UCH37. Both RPN13 and UCH37 have been implicated in human cancers, and inhibitors of the RPN2-RPN13 interaction are being developed as potential therapeutic anticancer agents. Our current study builds on the recognition that a residue central to the RPN2-RPN13 interaction, RPN2 Tyr-950, is phosphorylated in Jurkat cells. We found that the Tyr-950 phosphorylation enhances binding to RPN13. The crystal structure of the RPN2-RPN13 pTyr-950-ubiquitin complex was determined at 1.76-Å resolution and reveals specific interactions with positively charged side chains in RPN13 that explain how phosphorylation increases binding affinity without inducing conformational change. Mutagenesis and quantitative binding assays were then used to validate the crystallographic interface. Our findings support a model in which RPN13 recruitment to the proteasome is enhanced by phosphorylation of RPN2 Tyr-950, have important implications for efforts to develop specific inhibitors of the RPN2-RPN13 interaction, and suggest the existence of a previously unknown stress-response pathway.

PubMed: 31064842
DOI: 10.1074/jbc.AC119.008881

Experimental method

X-RAY DIFFRACTION (1.76 Å)