REQUIREMENTS FOR GREEN FLUORESCENT PROTEIN-DETECTION IN TRANSGENIC ZEBRAFISH EMBRYOS

We have generated transgenic (Tg) lines of zebrafish in which the gree n fluorescent protein (GFP)-encoding gfp cDNA is driven by the Xenopus laevis ef1 alpha enhancer/promoter, Tg embryos from most of these lin es show detectable fluorescence throughout their body. We have investi gated the copy number of the Tg genes in fluorescent and nonfluorescen t lines, in order to determine how this affects the production of dete ctable levels of GFP in the zebrafish embryo, Additionally, we have in jected purified recombinant GFP into embryos to determine the intracel lular GFP concentration required for detection, both when all of the c ells in the embryo contain GFP and when only a few do.