SUMO deconjugation is required for arsenic-triggered ubiquitylation of PML

Sci Signal. 2015 Jun 9;8(380):ra56. doi: 10.1126/scisignal.aaa3929.


Acute promyelocytic leukemia is characterized by a chromosomal translocation that produces an oncogenic fusion protein of the retinoic acid receptor α (RARα) and promyelocytic leukemia protein (PML). Arsenic trioxide chemotherapy of this cancer induces the PML moiety to organize nuclear bodies, where the oncoprotein is degraded. This process requires the participation of two SUMO paralogs (SUMO1 and SUMO2) to promote PML ubiquitylation mediated by the ubiquitin E3 ligase RNF4 and reorganization of PML nuclear bodies. We demonstrated that the ubiquitylation of PML required the SUMO deconjugation machinery, primarily the deconjugating enzyme SENP1, and was suppressed by expression of non-deconjugatable SUMO2. We hypothesized that constitutive SUMO2 conjugation and deconjugation occurred basally and that arsenic trioxide treatment caused the exchange of SUMO2 for SUMO1 on a fraction of Lys(65) in PML. On the basis of data obtained with mutational analysis and quantitative proteomics, we propose that the SUMO switch at Lys(65) of PML enhanced nuclear body formation, subsequent SUMO2 conjugation to Lys(160), and consequent RNF4-dependent ubiquitylation of PML. Our work provides insights into how the SUMO system achieves selective SUMO paralog modification and highlights the crucial role of SENPs in defining the specificity of SUMO signaling.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arsenic Trioxide
  • Arsenicals / pharmacology*
  • Blotting, Western
  • CHO Cells
  • COS Cells
  • Chlorocebus aethiops
  • Cricetinae
  • Cricetulus
  • Cysteine Endopeptidases
  • Endopeptidases / genetics
  • Endopeptidases / metabolism
  • HEK293 Cells
  • Humans
  • Lysine / genetics
  • Lysine / metabolism
  • Microscopy, Confocal
  • Molecular Sequence Data
  • Mutation
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Oxides / pharmacology*
  • Promyelocytic Leukemia Protein
  • RNA Interference
  • SUMO-1 Protein / genetics
  • SUMO-1 Protein / metabolism*
  • Signal Transduction / drug effects
  • Small Ubiquitin-Related Modifier Proteins / genetics
  • Small Ubiquitin-Related Modifier Proteins / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism*
  • Ubiquitination / drug effects


  • Arsenicals
  • Nuclear Proteins
  • Oxides
  • Promyelocytic Leukemia Protein
  • RNF4 protein, human
  • SUMO-1 Protein
  • SUMO1 protein, human
  • SUMO2 protein, human
  • Small Ubiquitin-Related Modifier Proteins
  • Transcription Factors
  • Tumor Suppressor Proteins
  • PML protein, human
  • Endopeptidases
  • SENP1 protein, human
  • Cysteine Endopeptidases
  • Lysine
  • Arsenic Trioxide