Physical mapping and promoter structure of the murine cAMP-specific phosphodiesterase pde4a gene

The Pde4a gene is a mammalian homolog of the dunce learning and memory gene of Drosophila melanogaster and encodes cAMP-specific phosphodiesterases, targets for drugs with antidepressant and anti-inflammatory actions in humans. We have analyzed the intron/exon and promoter structure of the murine Pde4a gene. Pde4a encodes at least two different transcripts, each generated by alternative mRNA splicing and the use of alternative promoters. The majority of Pde4a exons are tightly clustered at the 3' end of the gene. The 5' region of the gene contains at least one widely separated exon, which encodes the 5' end of a distinct mRNA transcript and contains a separate promoter and transcriptional start site. Analysis of YAC clones determined that the Pde4a gene maps to the 4-cM region of Chromosome (Chr) 9, close to Ldlr and Epor, in a region syntenic to human PDE4A.