PIAS proteins as regulators of small ubiquitin-related modifier (SUMO) modifications and transcription

Biochem Soc Trans. 2007 Dec;35(Pt 6):1405-8. doi: 10.1042/BST0351405.


Transcriptional activity of signal-dependent transcription factors, including nuclear receptors, relies on interacting co-regulator proteins, many of which possess protein-modifying activity. SUMOs (small ubiquitin-related modifiers) and their conjugation pathway components act as co-regulator proteins for numerous transcription factors that also are often targets for SUMO modification. PIAS [protein inhibitor of activated STAT (signal transducer and activator of transcription)] proteins promote SUMOylation in a manner that resembles the action of RING-type ubiquitin E3 ligases. PIAS proteins were initially named for their ability to interact with STAT proteins and inhibit their activity, but their interactions and functions are not restricted to the STATs. Moreover, PIAS proteins do not operate merely as SUMO E3s, since their co-regulator effects are often independent of their RING finger but dependent on their SIM (SUMO-interacting motif) or SAP (scaffold attachment factor-A/B/acinus/PIAS) domain capable of interacting with DNA. The modulator activity imparted by the PIAS/SUMO system involves altered subnuclear targeting and/or assembly of transcription complexes. PIAS proteins may act as platforms that facilitate both removal and recruitment of other regulatory proteins in the transcription complexes.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Protein Inhibitors of Activated STAT / chemistry
  • Protein Inhibitors of Activated STAT / physiology*
  • STAT Transcription Factors / metabolism
  • Small Ubiquitin-Related Modifier Proteins / metabolism*
  • Transcription, Genetic* / genetics
  • Transcription, Genetic* / physiology
  • Ubiquitin-Protein Ligases / metabolism


  • Protein Inhibitors of Activated STAT
  • STAT Transcription Factors
  • Small Ubiquitin-Related Modifier Proteins
  • Ubiquitin-Protein Ligases