
The deubiquitylating enzyme Ubp12 regulates Rad23-dependent proteasomal degradation
Author(s) -
Daniela Gödderz,
Tatiana A. Giovannucci,
Jana Laláková,
Victoria MenéndezBenito,
Nico P. Dantuma
Publication year - 2017
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.202622
Subject(s) - ubiquitin , biology , proteasome , saccharomyces cerevisiae , microbiology and biotechnology , proteolysis , ubiquitin ligase , biochemistry , hydrolase , protein degradation , dna repair , enzyme , yeast , dna , gene
The consecutive actions of the ubiquitin-selective segregase Cdc48 and the ubiquitin shuttle factor Rad23 result in the delivery of ubiquitylated proteins at the proteasome. Here, we show that the deubiquitylating enzyme Ubp12 interacts with Cdc48 and regulates proteasomal degradation of Rad23-dependent substrates. Overexpression of Ubp12 results in stabilization of Rad23-dependent substrates. We show that Ubp12 removes short ubiquitin chains from the N-terminal ubiquitin-like domain (UbL) of Rad23. Preventing ubiquitylation of Rad23 by substitution of lysine residues within the UbL domain, Rad23UbLK0, does not affect the non-proteolytic role of Rad23 in DNA repair but causes an increase in ubiquitylated cargo bound to the UBA2 domains of Rad23 and recapitulates the stabilization of Rad23-dependent substrates observed upon overexpression of Ubp12. Expression of Rad23UbLK0 or overexpression of Ubp12 impairs the ability of yeast to cope with proteotoxic stress consistent with inefficient clearance of misfolded proteins by the ubiquitin/proteasome system. Our data suggest that ubiquitylation of Rad23 plays a stimulatory role in the degradation of ubiquitylated substrates by the proteasome.