Protacs: chimeric molecules that target proteins to the Skp1-Cullin-F box complex for ubiquitination and degradation

Proc Natl Acad Sci U S A. 2001 Jul 17;98(15):8554-9. doi: 10.1073/pnas.141230798. Epub 2001 Jul 3.

Abstract

The intracellular levels of many proteins are regulated by ubiquitin-dependent proteolysis. One of the best-characterized enzymes that catalyzes the attachment of ubiquitin to proteins is a ubiquitin ligase complex, Skp1-Cullin-F box complex containing Hrt1 (SCF). We sought to artificially target a protein to the SCF complex for ubiquitination and degradation. To this end, we tested methionine aminopeptidase-2 (MetAP-2), which covalently binds the angiogenesis inhibitor ovalicin. A chimeric compound, protein-targeting chimeric molecule 1 (Protac-1), was synthesized to recruit MetAP-2 to SCF. One domain of Protac-1 contains the I kappa B alpha phosphopeptide that is recognized by the F-box protein beta-TRCP, whereas the other domain is composed of ovalicin. We show that MetAP-2 can be tethered to SCF(beta-TRCP), ubiquitinated, and degraded in a Protac-1-dependent manner. In the future, this approach may be useful for conditional inactivation of proteins, and for targeting disease-causing proteins for destruction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminopeptidases / metabolism*
  • Animals
  • Cell Extracts
  • Cell Line, Transformed
  • DNA-Binding Proteins / metabolism*
  • Humans
  • I-kappa B Proteins*
  • Metalloendopeptidases / metabolism*
  • NF-KappaB Inhibitor alpha
  • Ovum / metabolism
  • Peptide Synthases / metabolism*
  • Protein Binding
  • Recombinant Fusion Proteins / metabolism
  • SKP Cullin F-Box Protein Ligases
  • Ubiquitins / metabolism*
  • Xenopus laevis

Substances

  • Cell Extracts
  • DNA-Binding Proteins
  • I-kappa B Proteins
  • NFKBIA protein, human
  • Recombinant Fusion Proteins
  • Ubiquitins
  • NF-KappaB Inhibitor alpha
  • SKP Cullin F-Box Protein Ligases
  • Aminopeptidases
  • methionine aminopeptidase 2
  • Metalloendopeptidases
  • Peptide Synthases