Inhibition of thyrotropin-stimulated DNA synthesis by microinjection of inhibitors of cellular Ras and cyclic AMP-dependent protein kinase.

摘要: Microinjection of a dominant interfering mutant Ras (N17 Ras) caused significant reduction in thyrotropin (thyroid-stimulating hormone [TSH])-stimulated DNA synthesis rat thyroid cells. A similar was observed following injection the heat-stable protein kinase inhibitor cyclic AMP-dependent kinase. Coinjection both inhibitors almost completely abolished TSH-induced synthesis. In contrast to TSH, overexpression cellular did not stimulate expression AMP response element-regulated reporter gene. Similarly, N17 had no effect on TSH-stimulated gene expression. Moreover, stimulated levels presence or absence inhibitor. Together, these results suggest that Wistar cells, full mitogenic TSH requires and APK-dependent