is essential for normal mushroom body and wing development.

MEF2 (myocyte enhancer factor 2) transcription factors are found in the brain and muscle of insects and vertebrates and are essential for the differentiation of multiple cell types. We show that in the fruit fly , MEF2 is essential for the formation of mushroom bodies in the embryonic brain and for the normal development of wings in the adult. In embryos mutant for , there is a striking reduction in the number of mushroom body neurons and their axon bundles are not detectable.

The gene structure of the Drosophila melanogaster proto-oncogene, kayak, and its nested gene, fos-intronic gene.

We present herein a new model for the structure of the Drosophila kayak gene as well as preliminary data on the functional differences of its various isoforms. kayak is a homolog of the human proto-oncogene, c-fos. kayak has three different starts of transcription, and therefore promoters (P)kay-alpha, (P)kay-beta and (P)kay-gamma.

Phylogenetic and genomewide analyses suggest a functional relationship between kayak, the Drosophila fos homolog, and fig, a predicted protein phosphatase 2c nested within a kayak intron.

A gene located within the intron of a larger gene is an uncommon arrangement in any species. Few of these nested gene arrangements have been explored from an evolutionary perspective. Here we report a phylogenetic analysis of kayak (kay) and fos intron gene (fig), a divergently transcribed gene located in a kay intron, utilizing 12 Drosophila species.