A nuclear GFP/β-galactosidase fusion protein as a marker for morphogenesis in living Drosophila

Abstract

A general, non-invasive method to trace morphogenesis in living Drosophila was developed. To label specific cells, green fluorescence protein (GFP) of jellyfish Aequorea victoria was expressed by the Gal4-UAS system. Green fluorescence from GFP fused to the nuclear localization signal was detectable in polytene larval tissue, but not in diploid tissue. Further fusion to bacterial β-galactosidase produced GFPN-lacZ, which fluoresced brightly in several diploid larval and embryonic tissues. GFPN-lacZ was used to trace dynamic cell movement during the formation of the embryonic tracheal system. These results indicate that GFPN-lacZ can be used to mark specific cells to study cell movement and gene expression in living animals.