Patterns of conservation and divergence at the even-skipped locus of Drosophila

The even-skipped (eve) gene of Drosophila melanogaster has been intensively studied as a model for spatial and temporal control of gene expression, using in vitro and transgenic techniques. Here, the study of eve is extended, using evolutionary conservation of DNA sequences. Conservation of much of the protein, and of known regulatory elements, supports models for eve function and regulation that have previously been advanced, and extensive conservation found in noncoding sequences predicts that functional elements exist that have yet to be defined. In contrast, a part of the protein implicated in transcriptional repression has diverged extensively while preserving overall amino acid composition, highlighting potentially essential features of this domain. Also, the basal promoter has diverged extensively, indicating evolutionary flexibility of promoter function.