JNK phosphorylation of Bim-related members of the Bcl2 family induces Bax-dependent apoptosis
UMass Chan AffiliationsHoward Hughes Medical Institute and Program in Molecular Medicine
Keywords*Adaptor Proteins, Signal Transducing
Apoptosis Regulatory Proteins
DNA Mutational Analysis
Proto-Oncogene Proteins c-bcl-2
bcl-2-Associated X Protein
Medicine and Health Sciences
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AbstractThe c-Jun NH(2)-terminal kinase (JNK) is activated when cells are exposed to environmental stress, including UV radiation. Gene disruption studies demonstrate that JNK is essential for UV-stimulated apoptosis mediated by the mitochondrial pathway by a Bax/Bak-dependent mechanism. Here, we demonstrate that JNK phosphorylates two members of the BH3-only subgroup of Bcl2-related proteins (Bim and Bmf) that are normally sequestered by binding to dynein and myosin V motor complexes. Phosphorylation by JNK causes release from the motor complexes. These proapoptotic BH3-only proteins therefore provide a molecular link between the JNK signal transduction pathway and the Bax/Bak-dependent mitochondrial apoptotic machinery.
Proc Natl Acad Sci U S A. 2003 Mar 4;100(5):2432-7. Epub 2003 Feb 18. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/38943
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