Ubiquitin-associated (UBA) domains in Rad23 bind ubiquitin and promote inhibition of multi-ubiquitin chain assembly

EMBO Rep. 2001 Oct;2(10):933-8. doi: 10.1093/embo-reports/kve203. Epub 2001 Sep 24.

Abstract

Rad23 is a DNA repair protein that promotes the assembly of the nucleotide excision repair complex. Rad23 can interact with the 26S proteasome through an N-terminal ubiquitin-like domain, and inhibits the assembly of substrate-linked multi-ubiquitin (multi-Ub) chains in vitro and in vivo. Significantly, Rad23 can bind a proteolytic substrate that is conjugated to a few ubiquitin (Ub) moieties. We report here that two ubiquitin-associated (UBA) domains in Rad23 form non-covalent interactions with Ub. A mutant that lacked either UBA sequence was capable of blocking the assembly of substrate-linked multi-Ub chains, although a mutant that lacked both UBA domains was significantly impaired. These studies suggest that the interaction with Ub is required for Rad23 activity, and that other UBA-containing proteins may have a similar function.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Codon
  • DNA / metabolism
  • DNA Repair Enzymes
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Fungal Proteins / chemistry*
  • Fungal Proteins / metabolism*
  • Glutathione Transferase / metabolism
  • Molecular Sequence Data
  • Mutation
  • Oligonucleotides / metabolism
  • Protein Binding
  • Protein Structure, Tertiary
  • Sequence Homology, Amino Acid
  • Substrate Specificity
  • Ubiquitin / chemistry*
  • Ubiquitin / metabolism*

Substances

  • Codon
  • DNA-Binding Proteins
  • Fungal Proteins
  • Oligonucleotides
  • Ubiquitin
  • RAD23A protein, human
  • DNA
  • Glutathione Transferase
  • DNA Repair Enzymes