MDM2 promotes SUMO-2/3 modification of p53 to modulate transcriptional activity

Cell Cycle. 2011 Sep 15;10(18):3176-88. doi: 10.4161/cc.10.18.17436. Epub 2011 Sep 15.

Abstract

The tumor suppressor p53 is extensively regulated by post-translational modification, including modification by the small ubiquitin-related modifier SUMO. We show here that MDM2, previously shown to promote ubiquitin, Nedd8 and SUMO-1 modification of p53, can also enhance conjugation of endogenous SUMO-2/3 to p53. Sumoylation activity requires p53-MDM2 binding but does not depend on an intact RING finger. Both ARF and L11 can promote SUMO-2/3 conjugation of p53. However, unlike the previously described SUMO-1 conjugation of p53 by an MDM2-ARF complex, this activity does not depend on the ability of MDM2 to relocalize to the nucleolus. Interestingly, the SUMO consensus is not conserved in mouse p53, which is therefore not modified by SUMO-2/3. Finally, we show that conjugation of SUMO-2/3 to p53 correlates with a reduction of both activation and repression of a subset of p53-target genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Gene Expression Regulation, Neoplastic
  • HCT116 Cells
  • Humans
  • Immunoprecipitation
  • Mice
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Plasmids / genetics
  • Plasmids / metabolism
  • Protein Binding
  • Proto-Oncogene Proteins c-mdm2 / genetics
  • Proto-Oncogene Proteins c-mdm2 / metabolism*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism
  • Retroviridae / genetics
  • Retroviridae / metabolism
  • Sequence Alignment
  • Small Ubiquitin-Related Modifier Proteins / genetics
  • Small Ubiquitin-Related Modifier Proteins / metabolism*
  • Sumoylation
  • Transcriptional Activation
  • Transfection
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • Ubiquitins / genetics
  • Ubiquitins / metabolism*

Substances

  • Repressor Proteins
  • SUMO2 protein, human
  • SUMO3 protein, human
  • Small Ubiquitin-Related Modifier Proteins
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Ubiquitins
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2