Human aldolase C gene expression is regulated by adenosine 3',5'-cyclic monophosphate (cAMP) in PC12 cells

We have examined the effects of an adenosine 3',5'-cyclic monophosphate (cAMP) analog on human aldolase C gene expression in the rat pheochromocytoma cell line PC12. Incubation for 4 h with 500 microM 8-Br-cAMP increased aldolase C mRNA expression 2.5-fold and the expression was still above basal level 24 h later. Using transient transfection experiments we demonstrate that the distal element D in the promoter region of the human aldolase C gene, which binds a transcriptional activator (NGFI-B), is involved in this regulation. NGFI-B mRNA and protein expression were promptly (15 min) increased after 8-Br-cAMP treatment and precedes aldolase C mRNA increase (30 min). After 4 h of 8-Br-cAMP treatment, the binding of NGFI-B protein to the distal element D in the distal promoter region was increased twofold and this correlates with the increased expression of the clone that contains distal element D. These results indicate that the distal element D in the promoter region of the human aldolase C gene is the target of a cAMP-dependent regulation pathway.