title: JNK phosphorylation of 14-3-3 proteins regulates nuclear targeting of c-Abl in the apoptotic response to DNA damage.
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.
authors.affiliation: Department of Molecular Genetics, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan. yos.mgen@mri.tmd.ac.jp
authors.forename: Kiyotsugu
authors.initials: K
authors.lastname: Yoshida
authors.forename: Tomoko
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Tohru
authors.initials: T
authors.lastname: Natsume
authors.forename: Donald
authors.initials: D
authors.lastname: Kufe
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Miki
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism*; D002853:Chromatography, Liquid; D004249:DNA Damage; D049452:Green Fluorescent Proteins / Q000378:metabolism; D018922:HL-60 Cells; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism / Q000502:physiology*; D048670:MAP Kinase Kinase 4; D013058:Mass Spectrometry; D051379:Mice; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism / Q000502:physiology*; D008954:Models, Biological; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D017434:Protein Structure, Tertiary; D016315:Proto-Oncogene Proteins c-abl / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D013347:Subcellular Fractions; D014162:Transfection; D020298:U937 Cells
chemical_list: D048948:14-3-3 Proteins; D034741:RNA, Small Interfering; D049452:Green Fluorescent Proteins; D016315:Proto-Oncogene Proteins c-abl; D048031:JNK Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D020929:Mitogen-Activated Protein Kinase Kinases