GFP-tagged balancer chromosomes for Drosophila melanogaster

We constructed green fluorescent protein (GFP)-expressing balancer chromoso mes for each of the three major chromosomes of Drosophila melanogaster. Exp ression of GFP in these chromosomes is driven indirectly by a Kruppel (Kr) promoter, via the yeast GAL4-UAS regulatory system. GFP fluorescence can be seen in embryos as early as the germ band extension stage, and can also be seen in larvae, pupae, and adults. We show the patterns of GFP expression of these balancers and demonstrate the use of the balancers to identify hom ozygous progeny. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved .