Mechanisms of aluminium fluoride- and insulin-stimulated p33 mRNA accumulation in rat hepatoma cells: Involvement of a G protein and kinase action and demonstration of effects on mRNA turnover

Abstract The insulin signalling pathway to control nuclear p33 gene expression was examined. An AlF4-stimulated pertussin toxin-insensitive G protein was shown to be involved. The action of AlF4− was completely blocked by deferoxamine. Insulin action was markedly stimulated in the presence of AlF4−. cAMP and diacylglycerol concentrations were examined as possible regulators but no increases were detected. The effects of AlF4− and of insulin were completely inhibited by the general kinase inhibitor H-7. A second calcium calmodulin protein kinase inhibitor, W-7, had no detectable effect. Insulin and AlF4− were shown to stabilize p33 mRNA.