Role of p38 and JNK mitogen-activated protein kinases in the activation of ternary complex factors
UMass Chan AffiliationsProgram in Molecular Medicine
Department of Biochemistry and Molecular Biology
Calcium-Calmodulin-Dependent Protein Kinases
Gene Expression Regulation, Enzymologic
JNK Mitogen-Activated Protein Kinases
*Mitogen-Activated Protein Kinases
Receptor Protein-Tyrosine Kinases
ets-Domain Protein Elk-1
p38 Mitogen-Activated Protein Kinases
Medicine and Health Sciences
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AbstractThe transcription factors Elk-1 and SAP-1 bind together with serum response factor to the serum response element present in the c-fos promoter and mediate increased gene expression. The ERK, JNK, and p38 groups of mitogen-activated protein (MAP) kinases phosphorylate and activate Elk-1 in response to a variety of extracellular stimuli. In contrast, SAP-1 is activated by ERK and p38 MAP kinases but not by JNK. The proinflammatory cytokine interleukin-1 (IL-1) activates JNK and p38 MAP kinases and induces the transcriptional activity of Elk-1 and SAP-1. These effects of IL-1 appear to be mediated by Rho family GTPases. To examine the relative roles of the JNK and p38 MAP kinase pathways, we examined the effects of IL-1 on CHO and NIH 3T3 cells. Studies of NIH 3T3 cells demonstrated that both the JNK and p38 MAP kinases are required for IL-1-stimulated Elk-1 transcriptional activity, while only p38 MAP kinase contributes to IL-1-induced activation of SAP-1. In contrast, studies of CHO cells demonstrated that JNK (but not the p38 MAP kinase) is required for IL-1-stimulated Elk-1-dependent gene expression and that neither JNK nor p38 MAP kinase is required for IL-1 signaling to SAP-1. We conclude that (i) distinct MAP kinase signal transduction pathways mediate IL-1 signaling to ternary complex transcription factors (TCFs) in different cell types and (ii) individual TCFs show different responses to the JNK and p38 signaling pathways. The differential utilization of TCF proteins and MAP kinase signaling pathways represents a potential mechanism for the determination of cell-type-specific responses to extracellular stimuli.
SourceMol Cell Biol. 1997 May;17(5):2360-71.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/38586
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A mammalian scaffold complex that selectively mediates MAP kinase activationWhitmarsh, Alan J.; Cavanagh, Julie; Tournier, Cathy; Yasuda, Jun; Davis, Roger J. (1998-09-11)The c-Jun NH2-terminal kinase (JNK) group of mitogen-activated protein (MAP) kinases is activated by the exposure of cells to multiple forms of stress. A putative scaffold protein was identified that interacts with multiple components of the JNK signaling pathway, including the mixed-lineage group of MAP kinase kinase kinases (MLK), the MAP kinase kinase MKK7, and the MAP kinase JNK. This scaffold protein selectively enhanced JNK activation by the MLK signaling pathway. These data establish that a mammalian scaffold protein can mediate activation of a MAP kinase signaling pathway.
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