title: Cloning and characterization of novel PDE4D isoforms PDE4D6 and PDE4D7.
abstract: We report here the cloning and characterization of two novel PDE4D isoforms, PDE4D6 and PDE4D7. PDE4D6 is a supershort form and PDE4D7 a long form of PDE4D. In addition, we have identified another novel long-form variant, PDE4D8, in silico. Like other isoforms, PDE4D6 and PDE4D7 are differentially expressed. Expression of PDE4D6 is restricted to brain whereas PDE4D7 is widely expressed in many tissues. Baculovirus-expressed recombinant PDE4D6 and PDE4D7 enzymes have high affinity for cyclic AMP (cAMP) and are inhibited by rolipram. The activity of PDE4D7, not PDE4D6, is elevated by a protein kinase A (PKA)-dependent mechanism, presumably through phosphorylation of the conserved PKA site in the upstream conserved region 1 (UCR1) domain. In agreement with early reports, human PDE4D6 and PDE4D7 are localized on genomic fragments of chromosome 5. Examination of the promoter regions reveals multiple CREB binding sites upstream of the starting methionine (Met) of each gene, suggesting that the cAMP/PKA signaling pathway may regulate transcriptional expression of PDE4D6 and PDE4D7.
authors.affiliation: Discovery Research, Memory Pharmaceuticals Corp, 100 Philips Parkway, Montvale, NJ 07645, USA. wang@memorypharma.com
authors.forename: Daguang
authors.initials: D
authors.lastname: Wang
authors.forename: Chengjun
authors.initials: C
authors.lastname: Deng
authors.forename: Bozena
authors.initials: B
authors.lastname: Bugaj-Gaweda
authors.forename: May
authors.initials: M
authors.lastname: Kwan
authors.forename: Caryn
authors.initials: C
authors.lastname: Gunwaldsen
authors.forename: Chris
authors.initials: C
authors.lastname: Leonard
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Xin
authors.forename: Yinghe
authors.initials: Y
authors.lastname: Hu
authors.forename: Axel
authors.initials: A
authors.lastname: Unterbeck
authors.forename: Michael
authors.initials: M
authors.lastname: De Vivo
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D017398:Alternative Splicing / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D001667:Binding, Competitive / Q000187:drug effects; D015153:Blotting, Western; D020134:Catalytic Domain / Q000235:genetics; D002460:Cell Line; D003001:Cloning, Molecular; D017124:Conserved Sequence / Q000235:genetics; D000242:Cyclic AMP / Q000378:metabolism; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000494:pharmacology; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D004305:Dose-Response Relationship, Drug; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D007700:Kinetics; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D010766:Phosphorylation; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D051381:Rats; D020889:Rolipram / Q000494:pharmacology; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D018411:Spodoptera; D014162:Transfection
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D007527:Isoenzymes; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; C517376:PDE4D protein, human; D020889:Rolipram