Induction of c-fos mRNA in rat lymphoma Nb-2 cells.
Cyclosporin A, immunosuppressive agent, reversibly blocks the mitogenic effect of prolactin in rat lymphoma Nb-2 cells and removal from the medium leads to a rapid and transient induction of c-fos mRNA. Activators of protein kinase C, such as TPA, mellitin and phospholipase C and the calcium ionophore, A23187, induced c-fos mRNA in the presence or absence of cyclosporin A. Activators of the cAMP pathway such as forskolin, dBcAMP and cholera toxin failed to induce c-fos mRNA in the presence or absence of cyclosporin A. These results suggest that cyclosporin A may act at the level of protein kinase C.
Bajpai
A
A
Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City 66103.
Andrews
G K
GK
Ebner
K E
KE
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D003524:Cyclosporins / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects; D008223:Lymphoma / Q000235:genetics*; D008555:Melitten / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000494:pharmacology
D003524:Cyclosporins; D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D008555:Melitten; D000001:Calcimycin; D011493:Protein Kinase C; D010738:Type C Phospholipases; D013755:Tetradecanoylphorbol Acetate