Drosophila Adh: a promoter element expands the tissue specificity of an enhancer.

Drosophila alcohol dehydrogenase (Adh) genes are expressed in the fat body and in species-specific sets of other tissues during larval and adult development. The Drosophila mulleri Adh-1 gene is expressed in the larval fat body and in three other larval tissues. In this paper, we show that Adh-1 expression in multiple cell types is the result of synergistic interactions between fat body-specific enhancers and a specific Adh-1 promoter element.