Involvement of PIAS1 in the sumoylation of tumor suppressor p53

Mol Cell. 2001 Sep;8(3):713-8. doi: 10.1016/s1097-2765(01)00349-5.


Sumoylation of p53 by the ubiquitin-like protein, SUMO-1/sentrin/PIC1, has been shown to stimulate its transcriptional activation activity. The SUMO E3 ligase, a key enzyme in the recognition of substrates to be sumoylated, has not yet been identified. We isolated PIAS1 (protein inhibitor of activated STAT1) as a SUMO-1 binding protein by yeast two-hybrid screening. In addition, PIAS1 bound p53 and Ubc9, the E2 for SUMO. PIAS1 that was mutated in the RING finger-like domain bound p53 and SUMO-1, but not Ubc9. PIAS1 catalyzed the sumoylation of p53 both in U2OS cells and in vitro in a domain-dependent manner. These data suggest that PIAS1 functions as a SUMO ligase, or possibly as a tightly bound regulator of it, toward p53.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Cell Fractionation
  • Cell Line
  • Genes, Reporter / genetics
  • Humans
  • Immunoblotting
  • Ligases / metabolism
  • Molecular Sequence Data
  • Protein Binding
  • Protein Inhibitors of Activated STAT
  • Protein Structure, Tertiary
  • Proteins / chemistry
  • Proteins / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • SUMO-1 Protein
  • Saccharomyces cerevisiae / physiology
  • Sequence Alignment
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • Two-Hybrid System Techniques
  • Ubiquitin-Conjugating Enzymes*
  • Ubiquitins / metabolism*


  • Protein Inhibitors of Activated STAT
  • Proteins
  • Recombinant Fusion Proteins
  • SUMO-1 Protein
  • Tumor Suppressor Protein p53
  • Ubiquitins
  • Ubiquitin-Conjugating Enzymes
  • Ligases
  • ubiquitin-conjugating enzyme UBC9