Genetic Changes to a Transcriptional Silencer Element Confers Phenotypic Diversity within and between Drosophila Species
(A) Expression of ebony in the abdomen of a D. serrata male (UCSD “03” strain). (B) The entire upstream region of D. serrata ebony fused into a GFP reporter construct recapitulates the broad activation of ebony throughout the male posterior abdomen. (C) Chimeric reporter in which a 1 kb segment containing the D. serrata upstream silencer region was placed into the D. auraria dark strain reporter construct. This reporter lacks midline repression, indicating that the D. serrata upstream silencer was inactivated.