Developmental role of GABAB(1) receptors in Drosophila.

Previously, an RNA interference (RNAi) knockdown of GABAB(1) subunit in adult Drosophila was used for behavioral studies. Here we report on developmental deficits caused by embryonic Drosophila GABAB(1) RNAi and drug antagonism. Injecting embryos with CGP54626 (a GABAB receptor antagonist) reduced hatching and caused lethality. Similar effects were produced by injecting embryos with GABAB(1) double-stranded RNA (RNAi). The surviving GABAB(1) RNAi larvae were significantly smaller than controls and showed a peculiar phenotype; their tracheae were folded. Our results suggest that GABAB receptors are required for normal development and that the Drosophila model could be used to investigate the participating molecular mechanisms.