PHD domains and E3 ubiquitin ligases: viruses make the connection

Trends Cell Biol. 2003 Jan;13(1):7-12. doi: 10.1016/s0962-8924(02)00005-3.


PHD domains constitute a widely distributed subfamily of zinc fingers whose biochemical functions have been unclear until now. Recently, several PHD-containing viral proteins have been identified that promote immune evasion by downregulating proteins that govern immune recognition. Studies show that these viral regulators lead to ubiquitination of their targets by functioning as E3 ubiquitin ligases -- an activity that requires the PHD motif. These are the first examples linking the PHD domain to E3 activity, but the recent discovery of PHD-dependent E3 activity in the cellular kinase MEKK1 and the close structural relation of PHD domains to RING fingers hint that many other PHD proteins might share this activity.

Publication types

  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Humans
  • Ligases / chemistry*
  • Ligases / genetics
  • Ligases / metabolism
  • Ligases / physiology*
  • Molecular Sequence Data
  • Sequence Homology, Amino Acid
  • Ubiquitin-Protein Ligases
  • Ubiquitins / metabolism*
  • Viral Proteins / chemistry*
  • Viral Proteins / genetics
  • Viral Proteins / metabolism
  • Viral Proteins / physiology*
  • Viruses / enzymology*


  • Phd protein, Enterobacteria phage P1
  • Ubiquitins
  • Viral Proteins
  • Ubiquitin-Protein Ligases
  • Ligases