The NF-kappa B precursor p105 and the proto-oncogene product Bcl-3 are I kappa B molecules and control nuclear translocation of NF-kappa B

EMBO J. 1993 Jan;12(1):213-22. doi: 10.1002/j.1460-2075.1993.tb05647.x.

Abstract

We have examined the interaction of the NF-kappa B precursor p105 with NF-kappa B subunits. Similar to an I kappa B molecule, p105 associates in the cytoplasm with p50 or p65. Through this assembly, p105 efficiently blocks nuclear transfer of either subunit. Moreover, the p105 protein inhibits DNA binding of dimeric NF-kappa B subunits in a similar, but not identical, manner to its isolated C-terminal domain, which contains an ankyrin-like repeat domain (ARD). The proto-oncogene product Bcl-3 also controls nuclear translocation of p50, but not of p65. Hence, p50 can be retained in the cytoplasm via at least three distinct interactions: through direct interactions either with its own precursor, with Bcl-3 or indirectly through I kappa B alpha or -beta when attached to p65. We discuss a function of p105 as a cytoplasmic assembly unit for homo- and heteromeric NF-kappa B complexes and of Bcl-3 as an I kappa B with novel subunit specificity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies
  • B-Cell Lymphoma 3 Protein
  • Base Sequence
  • Cell Nucleus / metabolism*
  • Cells, Cultured
  • Cloning, Molecular
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Macromolecular Substances
  • Molecular Sequence Data
  • Molecular Weight
  • NF-kappa B / biosynthesis
  • NF-kappa B / genetics*
  • NF-kappa B / metabolism
  • Oligodeoxyribonucleotides
  • Peptides / chemical synthesis
  • Peptides / immunology
  • Protein Precursors / biosynthesis
  • Protein Precursors / genetics*
  • Protein Precursors / metabolism
  • Proto-Oncogene Proteins / biosynthesis
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogenes*
  • Recombinant Proteins / metabolism
  • Restriction Mapping
  • Transcription Factors

Substances

  • Antibodies
  • B-Cell Lymphoma 3 Protein
  • DNA-Binding Proteins
  • Macromolecular Substances
  • NF-kappa B
  • Oligodeoxyribonucleotides
  • Peptides
  • Protein Precursors
  • Proto-Oncogene Proteins
  • Recombinant Proteins
  • Transcription Factors