CHARACTERIZATION OF HUMAN AND MOUSE ROD CGMP PHOSPHODIESTERASE DELTA-SUBUNIT (PDE6D) AND CHROMOSOMAL LOCALIZATION OF THE HUMAN GENE

The mammalian multisubunit photoreceptor cGMP phosphodiesterase PDE al pha beta gamma(2) (PDE6 family) is a peripherally membrane-associated enzyme. A novel subunit, termed PDE delta (HGMW-approved symbol, PDE6D ; MW 17 kDa), is able to detach PDE partially from bovine rod outer se gment membranes under physiological conditions. Cloning of human and m ouse PDE delta cDNAs revealed that PDE delta is a nearly perfectly con served polypeptide of 150 amino acids that shows partial sequence homo logy to photoreceptor RG4 of unknown function. Multiple-species Southe rn blot analysis demonstrates that the PDE delta gene has been well co nserved during evolution and is detectable at high stringency in inver tebrates. The human and mouse genes are contained in less than 8 kb of genomic DNA and consist of four exons and three introns (0.7-4 kb in human, 0.7-2.2 kb in mouse). The PDE delta gene structure is identical to that of the C27H5.1 gene identified in the eyeless nematode Caenor habditis elegans. The human PDE delta gene (locus designation PDE6D) w as localized to the long arm of chromosome 2 (2q35-q36) by fluorescenc e in situ hybridization. By synteny, the mouse PDE epsilon gene is pre dicted to reside on chromosome 1. (C) 1998 Academic Press.