Human RelB (I-Rel) functions as a kappa B site-dependent transactivating member of the family of Rel-related proteins

Oncogene. 1994 Jun;9(6):1699-702.


RelB belongs to the family of Rel-related proteins, dimers of which determine NF-kappa B activity. The murine RelB protein has been reported to be a dimerizing partner in kappa B-binding complexes which are capable of transactivation. On the other hand, the I-Rel protein, the presumed human homolog of RelB, was proposed to be an inhibitor whose presence in dimeric complexes interfered with their kappa B binding and therefore interfered also with transactivation. We demonstrate that human RelB (I-Rel) forms with p50 and p52 (p50B) kappa B-binding heterodimeric complexes which potently transactivate kappa B-dependent constructs in transfection studies. It is concluded that human RelB (I-Rel) and murine RelB can both function as transactivators and that no significant species-specific differences exist.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • DNA / metabolism
  • Humans
  • Mice
  • Molecular Sequence Data
  • NF-kappa B / metabolism*
  • Proto-Oncogene Proteins*
  • Species Specificity
  • Trans-Activators / physiology*
  • Transcription Factor RelB
  • Transcription Factors / physiology*
  • Transfection


  • NF-kappa B
  • Proto-Oncogene Proteins
  • RELB protein, human
  • Relb protein, mouse
  • Trans-Activators
  • Transcription Factors
  • Transcription Factor RelB
  • DNA