Regulation of cAMP‐specific phosphodiesterases type 4B and 4D (PDE4) splice variants by cAMP signaling in primary cortical neurons

• Published in: Journal of neurochemistry Vol. 81; no. 4; pp. 745 - 757
• Main Authors: D'Sa, Carrol, Tolbert, Lara M., Conti, Marco, Duman, Ronald S.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.05.2002; Blackwell
• Subjects: 3',5'-Cyclic-AMP Phosphodiesterases - genetics; 3',5'-Cyclic-AMP Phosphodiesterases - metabolism; Alternative Splicing - drug effects; Alternative Splicing - physiology; Animals; Biochemistry and metabolism; Biological and medical sciences; Blotting, Western; Bucladesine - pharmacology; cAMP‐specific phosphodiesterase; Cells, Cultured; Central nervous system; Cerebral Cortex - cytology; Cerebral Cortex - metabolism; CREB; Cyclic AMP - metabolism; Cyclic AMP Response Element-Binding Protein - genetics; Cyclic AMP Response Element-Binding Protein - metabolism; Cyclic Nucleotide Phosphodiesterases, Type 4; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation - drug effects; Gene Expression Regulation - physiology; Isoenzymes - genetics; Isoenzymes - metabolism; Mutagenesis, Site-Directed; neurons; Neurons - cytology; Neurons - drug effects; Neurons - metabolism; Nucleic Acid Synthesis Inhibitors - pharmacology; Promoter Regions, Genetic - physiology; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - metabolism; rolipram; Signal Transduction - physiology; Transfection; Vertebrates: nervous system and sense organs; Cerebral cortex; Rat; Transcription promoter; Rodentia; Central nervous system; Cyclic AMP; Phosphodiesterase IV; Gene expression; In vitro; Protein; Signal transduction; Vertebrata; Mammalia; Neuron; Transcription factor CREB; Brain (vertebrata)
• ISSN: 0022-3042; 1471-4159
• DOI: 10.1046/j.1471-4159.2002.00878.x

This study examined the regulation of all known phosphodiesterase (PDE) type PDE4A, PDE4B and PDE4D splice variants in cortical neurons by cAMP signaling. Treatment with dibutyryl‐cAMP (db‐cAMP) caused the induction of two of the known splice variants, PDE4B2 and PDE4D1/PDE4D2. Although the splice variants PDE4A1, PDE4A5/PDE4A10, PDE4B3, PDE4B1, PDE4D3 and PDE4D4 were present in cortical neurons, their mRNA was not regulated at the transcriptional level by db‐cAMP. To assess the increase in PDE4B2 and PDE4D1/D2 mRNA expression, the promoters containing these genes were characterized. Transcription from both promoters was stimulated by db‐cAMP. Because chronic antidepressant treatment increases PDE4B, and not PDE4D, mRNA expression, we focused on the regulation of the PDE4B2 promoter by cAMP and CREB. Dominant negative mutants of CREB suppressed PDE4B2 promoter activity and a constitutively active form of CREB robustly stimulated it. These data demonstrate that in cortical neurons, a short PDE4B2 intronic promoter is regulated by CREB, confers cAMP responsitivity and directs PDE4B2 mRNA and protein expression.