Genetic Interactions Between Drosophila sialyltransferase and β1,4-N-acetylgalactosaminyltransferase-A Genes Indicate Their Involvement in the Same Pathway

Sialylated glycans play a prominent role in the Drosophila nervous system where they are involved in the regulation of neural transmission. However, the functional pathway of sialylation in invertebrates, including Drosophila, remains largely unknown. Here we used a combination of genetic and behavioral approaches to shed light on the Drosophila sialylation pathway. We examined genetic interactions between Drosophila sialyltransferase (DSiaT) and beta 1,4-N-acetylgalactosaminyltransferase (beta 4GalNAcT) genes. Our results indicated that beta 4GalNAcTA and DSiaT cooperate within the same functional pathway that regulates neural transmission. We found that beta 4GalNAcTA is epistatic to DSiaT. Our data suggest an intriguing possibility that beta 4GalNAcTA may participate in the biosynthesis of sialylated glycans.