Segmental distribution of bithorax complex proteins during Drosophila development

Abstract
The Ubx and bxd transcription units comprise a single functional domain in the bithorax complex of D. melanogaster. The segmental distributions and nuclear localization of proteins encoded by the Ubx unit were determined by immunofluorescence staining with antibodies raised against a fusion protein containing Ubx coding sequences. Wild-type and mutant distributions are consistent with a model in which the protein-coding functions of the domain derive from the Ubx unit and are regulated by the bxd unit.