Involvement of three intracellular messenger systems, protein kinase C, calcium ion and cyclic AMP, in the regulation of c‐fos gene expression in Swiss 3T3 cells

Abstract
In quiescent cultures of Swiss 3T3 cells, platelet-derived growth factor or fibroblast growth factor known to induce both protein kinase C activation and Ca2+ mobilization raised c-fos mRNA. This action of the growth factors was mimicked by the specific activators for protein kinase C, such as phorbol esters and a membrane-permeable synthetic diacylglycerol, and also by the Ca2+ ionophores, such as A23187 and ionomycin. Prostaglandin E1 known to elevate cyclic AMP also raised c-fos mRNA, and this action was mimicked by 8-bromo-cyclic AMP, dibutyryl cyclic AMP and forskolin. These results suggest that expression of the c-fos gene is regulated by three different intracellular messenger systems, protein kinase C, Ca2+ and cyclic AMP, in Swiss 3T3 cells