UbcH5 Interacts with Substrates to Participate in Lysine Selection with the E3 Ubiquitin Ligase CHIP

Adam Kanack, Vinayak Vittal, Holly Haver, Theodore Keppel, Rebekah L. Gundry, Rachel E. Klevit, Kenneth Matthew Scaglione

Research output: Contribution to journalArticlepeer-review

Abstract

The E3 ubiquitin ligase C-terminus of Hsc70 interacting protein (CHIP) plays a critical role in regulating the ubiquitin-dependent degradation of misfolded proteins. CHIP mediates the ubiquitination of the α-amino-terminus of substrates with the E2 Ube2w and facilitates the ubiquitination of lysine residues with the E2 UbcH5. While it is known that Ube2w directly interacts with the disordered regions at the N-terminus of its substrates, it is unclear how CHIP and UbcH5 mediate substrate lysine selection. Here, we have decoupled the contributions of the E2, UbcH5, and the E3, CHIP, in ubiquitin transfer. We show that UbcH5 selects substrate lysine residues independent of CHIP, and that CHIP participates in lysine selection by fine-tuning the subset of substrate lysines that are ubiquitinated. We also identify lysine 128 near the C-terminus of UbcH5 as a critical residue for the efficient ubiquitin transfer by UbcH5 in both the presence and absence of CHIP. Together, these data demonstrate an important role of the UbcH5/substrate interactions in mediating the efficient ubiquitin transfer by the CHIP/UbcH5 complex.

Original languageEnglish (US)
Pages (from-to)2078-2088
Number of pages11
JournalBiochemistry
Volume59
Issue number22
DOIs
StatePublished - Jun 9 2020

ASJC Scopus subject areas

  • Biochemistry

Fingerprint Dive into the research topics of 'UbcH5 Interacts with Substrates to Participate in Lysine Selection with the E3 Ubiquitin Ligase CHIP'. Together they form a unique fingerprint.

Cite this