Insulin activates nuclear factor kappa B in mammalian cells through a Raf-1-mediated pathway

J Biol Chem. 1995 Oct 13;270(41):24435-41. doi: 10.1074/jbc.270.41.24435.

Abstract

We examined the effect of insulin on nuclear factor kappa B (NF-kappa B) activity in Chinese ovary (CHO) cells overexpressing wild-type (CHO-R cells) or -defective insulin receptors mutated at Tyr1162 and Tyr1163 autophosphorylation sites (CHO-Y2 cells). In CHO-R cells, insulin caused a specific, time-, and concentration-dependent activation of NF-kappa B. The insulin-induced DNA-binding complex was identified as the p50/p65 heterodimer. Insulin activation of NF-kappa B: 1) was related to insulin receptor number and tyrosine kinase activity since it was markedly reduced in parental CHO cells which proved to respond to insulin growth factor-1 and phorbol 12-myristate 13-acetate (PMA) activation, and was dramatically decreased in CHO-Y2 cells; 2) persisted in the presence of cycloheximide and was blocked by pyrrolidine dithiocarbamate, aspirin and sodium salicylate, three compounds interfering with I kappa B degradation and/or NF-kappa B.I kappa B complex dissociation; 3) was independent of both PMA-sensitive and atypical (zeta) protein kinases C; and 4) was dependent on Raf-1 kinase activity since insulin-stimulated NF-kappa B DNA binding activity was inhibited by 8-bromo-cAMP, a Raf-1 kinase inhibitor. Moreover, insulin activation of NF-kappa B-driven luciferase reporter gene expression was blocked in CHO-R cells expressing a Raf-1 dominant negative mutant. This is the first evidence that insulin activates NF-kappa B in mammalian cells through a post-translational mechanism requiring both insulin receptor tyrosine kinase and Raf-1 kinase activities.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Bromo Cyclic Adenosine Monophosphate / pharmacology
  • Animals
  • Antioxidants / pharmacology
  • Aspirin / pharmacology
  • Base Sequence
  • Binding Sites
  • CHO Cells
  • Cricetinae
  • Cycloheximide / pharmacology
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Insulin / pharmacology*
  • Insulin-Like Growth Factor I / pharmacology
  • Kinetics
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • NF-kappa B / isolation & purification
  • NF-kappa B / metabolism*
  • Oligonucleotide Probes
  • Phosphorylation
  • Point Mutation
  • Protein Binding
  • Protein Serine-Threonine Kinases / antagonists & inhibitors
  • Protein Serine-Threonine Kinases / metabolism*
  • Proto-Oncogene Proteins / antagonists & inhibitors
  • Proto-Oncogene Proteins / isolation & purification
  • Proto-Oncogene Proteins / metabolism*
  • Proto-Oncogene Proteins c-raf
  • Pyrrolidines / pharmacology
  • Receptor, Insulin / biosynthesis
  • Receptor, Insulin / physiology*
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / metabolism
  • Signal Transduction / drug effects
  • Sodium Salicylate / pharmacology
  • Tetradecanoylphorbol Acetate / pharmacology
  • Thiocarbamates / pharmacology
  • Transcription Factor RelB
  • Transcription Factors*
  • Transfection
  • Tyrosine

Substances

  • Antioxidants
  • Enzyme Inhibitors
  • Insulin
  • NF-kappa B
  • Oligonucleotide Probes
  • Proto-Oncogene Proteins
  • Pyrrolidines
  • RELB protein, human
  • Recombinant Proteins
  • Thiocarbamates
  • Transcription Factors
  • Transcription Factor RelB
  • 8-Bromo Cyclic Adenosine Monophosphate
  • pyrrolidine dithiocarbamic acid
  • Tyrosine
  • Insulin-Like Growth Factor I
  • Cycloheximide
  • Receptor, Insulin
  • Protein Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-raf
  • Tetradecanoylphorbol Acetate
  • Aspirin
  • Sodium Salicylate