Cloning and characterization of mammalian homologs of the Drosophila dunce+ gene.
A probe representing the Drosophila dunce+ (dnc+) gene, the structural gene for a cAMP phosphodiesterase (PDEase), detects homologous sequences in many different organisms, including mouse, rat, and human. Genomic and cDNA clones representing a homolog of the Drosophila dnc+ gene were isolated from rat libraries and characterized. This gene has been named ratdnc-1. One cDNA clone defines a large open reading frame of approximately 1.8 kilobases (kb), predicting a protein sequence of 610 amino acids with significant homology to a conserved domain of approximately 275 residues found in most other PDEases. The amino acid identity value to the Drosophila cAMP PDEase within this domain is a striking 75%. Other cDNA clones show blocks of sequence divergence from this cDNA clone close to the predicted N terminus, indicating the potential existence of a family of related enzymes encoded by alternatively spliced messenger RNAs from ratdnc-1. Genomic blotting experiments suggest the existence of at least one other rat gene with homology to ratdnc-1. RNAs homologous to ratdnc-1 are heterogeneous in size between tissues, with heart containing a major transcript of 4.4 kb and brain one of 4.0 kb. The potential identity of the product of the ratdnc-1 gene with known PDEases is discussed.
Davis
R L
RL
Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030.
Takayasu
H
H
Eberwine
M
M
Myres
J
J
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004331:Drosophila melanogaster / Q000201:enzymology / Q000235:genetics; D005786:Gene Expression Regulation; D008568:Memory / Q000502:physiology; D008969:Molecular Sequence Data; D051381:Rats; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D014018:Tissue Distribution
D004247:DNA; D015105:3',5'-Cyclic-AMP Phosphodiesterases