Complex formation and cooperation of protein kinase C theta and Akt1/protein kinase B alpha in the NF-kappa B transactivation cascade in Jurkat T cells

J Biol Chem. 2001 Aug 24;276(34):31627-34. doi: 10.1074/jbc.M103098200. Epub 2001 Jun 15.

Abstract

Protein kinase C theta (PKC theta) is known to induce NF-kappa B, an essential transcriptional element in T cell receptor/CD28-mediated interleukin-2 production but also T cell survival. Here we provide evidence that PKC theta is physically and functionally coupled to Akt1 in this signaling pathway. First, T cell receptor/CD3 ligation was sufficient to induce activation as well as plasma membrane recruitment of PKC theta. Second, PKC theta selectively cooperated with Akt1, known to act downstream of CD28 co-receptor signaling, in activating a NF-kappa B reporter in T cells. Third, Akt1 function was shown to be required for PKC theta-mediated NF-kappa B transactivation. Fourth, PKC theta co-immunoprecipitated with Akt1; however, neither Akt1 nor PKC theta served as a prominent substrate for each other in vitro as well as in intact T cells. Finally, plasma membrane targeting of PKC theta and Akt1 exerted synergistic transactivation of the I-kappa B kinase beta/inhibitor of NF-kappa B/NF-kappa B signaling cascade independent of T cell activation. Taken together, these findings suggest a direct cross-talk between PKC theta and Akt1 in Jurkat T cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Catalysis
  • DNA Primers
  • Enzyme Activation
  • Humans
  • Isoenzymes / genetics
  • Isoenzymes / metabolism*
  • Jurkat Cells
  • NF-kappa B / metabolism*
  • Protein Kinase C / genetics
  • Protein Kinase C / metabolism*
  • Protein Kinase C-theta
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • Proto-Oncogene Proteins c-akt
  • Proto-Oncogene Proteins*
  • Recombinant Fusion Proteins / metabolism
  • Signal Transduction
  • Transcriptional Activation*

Substances

  • DNA Primers
  • Isoenzymes
  • NF-kappa B
  • Proto-Oncogene Proteins
  • Recombinant Fusion Proteins
  • AKT1 protein, human
  • Protein-Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • PRKCQ protein, human
  • Protein Kinase C
  • Protein Kinase C-theta