Isolation and chromosomal localization of two human CDP-diacylglycerol synthase (CDS) genes

Phototransduction in Drosophila is a phosphoinositide-mediated signaling pathway. Phosphatidylinositol 4,5-bisphosphate (PIP2) plays a central role in this process, and its levels are tightly regulated. A photoreceptor-specific form of the enzyme CDP-diacylglycerol synthase (CDS), which catalyzes the formation of CDP-diacylglycerol from phosphatidic acid, is a key regulator of the amount of PIP2 available for signaling. cds mutants develop light-induced retinal degeneration. As part of a search for novel genes that may be involved in eye disease in human, using Drosophila phototransduction genes as a model system, two human CDP-diacylglycerol synthase genes (CDS1 and CDS2) were cloned and sequenced. Radiation hybrid panel mapping and fluorescence in situ hybridization were used to localize the genes to chromosomes 4q21 and 20p13. As yet, no known retinal diseases map to either of these regions.