Dorsal , an Embryonic Polarity Gene in Drosophila , Is Homologous to the Vertebrate Proto-Oncogene, c- rel

The Drosophila gene, dorsal , is a maternal effect locus that is essential for the establishment of dorsal-ventral polarity in the developing embryo. The dorsal protein was predicted from the complementary DNA sequence; it is almost 50 percent identical, over an extensive region, to the protein encoded by the avian oncogene v- rel , its cellular homolog, c- rel , and a human c- rel fragment. The oncogene v- rel is highly oncogenic in avian lymphoid, spleen, and bone marrow cells.