A ceramide analogue (PDMP) inhibits glycolipid synthesis in fish embryos

Glycolipids were depleted from medaka embryos using 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), an inhibitor of glucosylceramide synthetase. Embryos cultured in the presence of 20 microM PDMP exhibited a dramatic decline in glycolipid synthesis and cell surface expression. Metabolic labeling of glucosylceramide declined by 87% on Days 3-6 of development and 72% on Days 7-10 (hatching occurred on Day 10). In parallel, PDMP-treated embryos exhibited a striking loss of several tissue-specific glycolipid antigens, including 9-O-acetyl GD3 from brain and retina, GT3/GQ1C from brain, neural tube, and retina, and sulfated glycolipid from skin and gut. Despite these changes in glycolipid expression, PDMP-treated embryos were fully viable with no evidence of developmental abnormality. PDMP appears to provide a useful tool for identifying glycolipid antigens in embryos and investigating their role in development.