Candidate proto-oncogene bcl-3 encodes a subunit-specific inhibitor of transcription factor NF-kappa B

Nature. 1992 Aug 13;358(6387):597-9. doi: 10.1038/358597a0.


The NF-kappa B subunits p50 and p65 and the product of the rel proto-oncogene are members of a growing class of transcription factors with a unique DNA-binding and dimerization domain. Nuclear transfer of each of these factors is controlled by cytoplasmic inhibitors, and regulated by specific stimuli. The inhibitors I kappa B-alpha and -beta and pp40 recognize either p65 or the c-rel protein. We show here that the proto-oncogene bcl-3, believed to be involved in certain human B-cell leukaemias, encodes a protein that functions as an I kappa B-like molecule for native NF-kappa B but is specific for the p50 subunit. The ankyrin repeat domain of the bcl-3 product is shown to mediate complex formation with NF-kappa B dimers by contracting the conserved dimerization domain of NF-kappa B.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • B-Cell Lymphoma 3 Protein
  • Cell Nucleus / metabolism
  • Chromatography, Affinity
  • Chromosome Deletion
  • Cloning, Molecular
  • DNA-Binding Proteins / metabolism*
  • HeLa Cells
  • Host Cell Factor C1
  • Humans
  • Macromolecular Substances
  • NF-kappa B / antagonists & inhibitors*
  • Octamer Transcription Factor-1
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins / metabolism*
  • Proto-Oncogenes*
  • Recombinant Proteins / metabolism
  • Repetitive Sequences, Nucleic Acid
  • Tetradecanoylphorbol Acetate / pharmacology
  • Transcription Factors / metabolism*


  • B-Cell Lymphoma 3 Protein
  • BCL3 protein, human
  • DNA-Binding Proteins
  • HCFC1 protein, human
  • Host Cell Factor C1
  • Macromolecular Substances
  • NF-kappa B
  • Octamer Transcription Factor-1
  • POU2F1 protein, human
  • Proto-Oncogene Proteins
  • Recombinant Proteins
  • Transcription Factors
  • Tetradecanoylphorbol Acetate