Characterization of the cDNA and Gene Encoding Human PDE3B, the cGIP1 Isoform of the Human Cyclic GMP-Inhibited Cyclic Nucleotide Phosphodiesterase Family

Two distinct PDE3 [cyclic GMP-inhibited cyclic nucleotide phosphodiesterase (cGI PDE)] isoforms, cGIP1 and cGIP2, have been identified. Here we report cloning of the cDNA and gene encoding human (H)cGIP1 (classified as PDE3B). The cDNA encodes a protein of 1112 amino acids (∼123 kDa). Northern blots indicate that its mRNA is expressed in several adipose tissue depots. The human PDE3B gene is composed of 16 exons spanning more than 114 kb and was localized to chromosome 11p15 byin situhybridization. Exon/intron boundaries were determined, and genetic polymorphism, confirmed by single-strand conformational polymorphism of DNA from 25 healthy subjects, was demonstrated in exon 4 at nucleotide 1389 (A/G). Two polymorphic dinucleotide repeat sequences were identified in introns 5 and 12.