Abstract
An increase in cellular levels of cyclic nucleotides activates serine/threonine-dependent kinases that lead to diverse physiological effects. Recently we reported the activation of the p38 mitogen-activated protein kinase (MAPK) pathway in neutrophils by a cGMP-dependent mechanism. In this study we demonstrated that exogenously supplied nitric oxide leads to activation of p38 MAPK in 293T fibroblasts. Phosphorylation of p38 corresponded with an increase in ATF-2-dependent gene expression. The effect of nitric oxide was mimicked by addition of 8-bromo-cGMP, indicating that activation of soluble guanylyl cyclase was involved. The importance of cGMP- dependent protein kinase in the activation of p38 MAPK by nitric oxide in 293T cells was assessed in a transfection based assay. Overexpression of cGMP-dependent protein kinase-1α caused phosphorylation of p38 in these cells and potentiated the effectiveness of cGMP. Overexpression of a catalytically inactive mutant form of this enzyme (T516A) blocked the ability of both nitric oxide and 8-bromo-cGMP to activate p38 as measured by both p38 phosphorylation and ATF-2 driven gene expression. Together, these data demonstrate that nitric oxide stimulates a novel pathway leading to activation of p38 MAPK that requires activation of cGMP-dependent protein kinase.
Original language | English (US) |
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Pages (from-to) | 2811-2816 |
Number of pages | 6 |
Journal | Journal of Biological Chemistry |
Volume | 275 |
Issue number | 4 |
DOIs | |
State | Published - Jan 28 2000 |
Externally published | Yes |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology