Fig. 1. The GAL4/UAS transplantation system. (A) Single cells are transplanted from UAS-GFP donors into da-GAL4 recipients at the blastoderm stage. After differentiation, GFP expression (green) is expected only in those syncytia that contain both donor- and recipient-derived nuclei. (B) To detect all descendants of the transplanted cell, the UAS-GFP donor embryos were labelled with the fluorescent dye RITC-dextran (red) at the preblastoderm stage before the transplantation. In the differentiated da-GAL4 recipients all mononuclear tissues, such as the fat body, generated by the descendants of the transplanted cell are solely labelled by RITC-dextran (red). Syncytia containing donor- and recipient-derived nuclei, like somatic muscles, exhibit an additional GFP expression (yellow indicates fluorescence superimposition of GFP and RITC-dextran).
