Molecular cloning and characterization of a novel Rel/NF-kappa B family member displaying structural and functional homology to NF-kappa B p50/p105

DNA Cell Biol. 1992 Sep;11(7):523-37. doi: 10.1089/dna.1992.11.523.


The NF-kappa B transcription factor has been implicated in the inducible expression of many genes, including inflammatory, immune, and acute-phase response genes. NF-kappa B consists of two subunits, 50K and 65K polypeptides. The genes encoding p50 and p65 have sequence similarities with the c-rel proto-oncogene and the Drosophila maternal effect gene dorsal. We describe the cloning and characterization of a novel rel-related gene encoding a 98K product that shares extensive homology with the p105 precursor of the NF-kappa B p50 protein, containing both a Rel homology and SWI6/ankyrin repeat domain. We demonstrate that p98 is proteolytically processed in vivo to generate a 55K polypeptide, which binds to kappa B sites. p55 is capable of forming heterocomplexes with other Rel/NF-kappa B family members, which can bind to kappa B motifs in vitro, and stimulate transcription of reporter genes containing these cis-elements in vivo. The identification of a homolog for NF-kappa B p50/p105, termed p55/p98, gives further support to the idea that NF-kappa B is a collection of structurally related complexes of which contribute to the pleiotropic regulatory processes originally assigned to NF-kappa B.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Ankyrins / chemistry
  • Ankyrins / genetics
  • Base Sequence
  • Cell Line
  • Cloning, Molecular
  • DNA
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • HeLa Cells
  • Humans
  • Molecular Sequence Data
  • Multigene Family*
  • NF-kappa B / chemistry
  • NF-kappa B / genetics*
  • NF-kappa B p52 Subunit
  • Neoplastic Stem Cells
  • Precipitin Tests
  • Protein Processing, Post-Translational
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins / chemistry
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins c-rel
  • Regulatory Sequences, Nucleic Acid
  • Sequence Homology
  • Transcription, Genetic


  • Ankyrins
  • DNA-Binding Proteins
  • MAS1 protein, human
  • NF-kappa B
  • NF-kappa B p52 Subunit
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-rel
  • DNA