The Drosophila ebony gene is closely related to microbial peptide synthetases and shows specific cuticle and nervous system expression.

The previously detected ebony (e) locus (Caizzi et al., 1987) consists of a complex gene structure that is divided into seven exons. An open reading frame encoding the putative Ebony protein of 98.5 kDa exhibits homology to a family of peptide synthetases (Stachelhaus and Marahiel, 1995), in good correlation with the proposed function as beta-alanyl-dopamine synthetase. Multiple ebony transcripts are detected throughout development. P-factor mediated transformation of genomic DNA rescues the cuticle, electrophysiological and behavioural phenotypes. Fusion of the ebony reading frame with that of beta-galactosidase of E. coli reveals expression in cuticle and nervous system. Strong staining in the first and, to a lesser extent, in the second optic neuropile may reflect the pronounced visual defect observed in ebony mutants. In addition, weak central brain and thoracic ganglion expression is detected in flies. Conservation of a multidomain protein structure known from peptide synthetases should have functional implications on the putative reaction mechanism of peptide bond formation.