JNK phosphorylation of 14-3-3 proteins regulates nuclear targeting of c-Abl in the apoptotic response to DNA damage

Nat Cell Biol. 2005 Mar;7(3):278-85. doi: 10.1038/ncb1228.

Abstract

The ubiquitously expressed c-Abl tyrosine kinase localizes to the cytoplasm and nucleus. Nuclear c-Abl is activated by diverse genotoxic agents and induces apoptosis; however, the mechanisms that are responsible for nuclear targeting of c-Abl remain unclear. Here, we show that cytoplasmic c-Abl is targeted to the nucleus in the DNA damage response. The results show that c-Abl is sequestered into the cytoplasm by binding to 14-3-3 proteins. Phosphorylation of c-Abl on Thr 735 functions as a site for direct binding to 14-3-3 proteins. We also show that, in response to DNA damage, activation of the c-Jun N-terminal kinase (Jnk) induces phosphorylation of 14-3-3 proteins and their release from c-Abl. Together with these results, expression of an unphosphorylated 14-3-3 mutant attenuates DNA-damage-induced nuclear import of c-Abl and apoptosis. These findings indicate that 14-3-3 proteins are pivotal regulators of intracellular c-Abl localization and of the apoptotic response to genotoxic stress.

Publication types

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

MeSH terms

  • 14-3-3 Proteins / metabolism
  • 14-3-3 Proteins / physiology*
  • Animals
  • Apoptosis*
  • Cell Line
  • Cell Line, Tumor
  • Cell Nucleus / metabolism*
  • Chromatography, Liquid
  • DNA Damage*
  • Green Fluorescent Proteins / metabolism
  • HL-60 Cells
  • HeLa Cells
  • Humans
  • Immunoblotting
  • Immunoprecipitation
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • JNK Mitogen-Activated Protein Kinases / physiology*
  • MAP Kinase Kinase 4
  • Mass Spectrometry
  • Mice
  • Mitogen-Activated Protein Kinase Kinases / metabolism
  • Mitogen-Activated Protein Kinase Kinases / physiology*
  • Models, Biological
  • Phosphorylation
  • Plasmids / metabolism
  • Protein Structure, Tertiary
  • Proto-Oncogene Proteins c-abl / metabolism*
  • RNA, Small Interfering / metabolism
  • Subcellular Fractions
  • Transfection
  • U937 Cells

Substances

  • 14-3-3 Proteins
  • RNA, Small Interfering
  • Green Fluorescent Proteins
  • Proto-Oncogene Proteins c-abl
  • JNK Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase 4
  • Mitogen-Activated Protein Kinase Kinases