Homoeotic genes

Abstract

Region specific differentiation in Drosophila, (and possibly in many other higher organisms), is controlled by the activity of families of transcription factors encoded by the homoeotic genes. In Drosophila these genes are clustered in two complexes: the Antennapedia complex is responsible for directing the differentiation of the head and thoracic body segments whereas the bithorax complex controls the differentiation of the thorax and abdomen. The precise way in which these genes work is still a mystery but both the levels and combinations of gene activities play an important role in directing the development of individual segments.