First Author | Boyce M | Year | 2008 |
Journal | Cell Death Differ | Volume | 15 |
Issue | 3 | Pages | 589-99 |
PubMed ID | 18188169 | Mgi Jnum | J:146381 |
Mgi Id | MGI:3837503 | Doi | 10.1038/sj.cdd.4402296 |
Citation | Boyce M, et al. (2008) A pharmacoproteomic approach implicates eukaryotic elongation factor 2 kinase in ER stress-induced cell death. Cell Death Differ 15(3):589-99 |
abstractText | Apoptosis triggered by endoplasmic reticulum (ER) stress has been implicated in many diseases but its cellular regulation remains poorly understood. Previously, we identified salubrinal (sal), a small molecule that protects cells from ER stress-induced apoptosis by selectively activating a subset of endogenous ER stress-signaling events. Here, we use sal as a probe in a proteomic approach to discover new information about the endogenous cellular response to ER stress. We show that sal induces phosphorylation of the translation elongation factor eukaryotic translation elongation factor 2 (eEF-2), an event that depends on eEF-2 kinase (eEF-2K). ER stress itself also induces eEF-2K-dependent eEF-2 phosphorylation, and this pathway promotes translational arrest and cell death in this context, identifying eEF-2K as a hitherto unknown regulator of ER stress-induced apoptosis. Finally, we use both sal and ER stress models to show that eEF-2 phosphorylation can be activated by at least two signaling mechanisms. Our work identifies eEF-2K as a new component of the ER stress response and underlines the utility of novel small molecules in discovering new cell biology. |