CIS-ACTING SEQUENCES CONTRIBUTING TO EXPRESSION OF THE DROSOPHILA-AFFINIDISJUNCTA ADH GENE IN BOTH LARVAE AND ADULTS

To characterize the cis-acting sequences required for expression of th e alcohol dehydrogenase (Adh) gene of the Hawaiian picture-winged frui t fly Drosophila affinidisjuncta, germ-line transformation was used to introduce altered forms of this gene into Drosophila melanogaster, Ge nes were constructed lacking regions corresponding to known or putativ e regulatory elements within the D. melanogaster gene as well as to se quences previously shown to be required for expression of the D. affin idisjuncta gene in the larval fat body as assayed by transient transfo rmation. Measurement of alcohol dehydrogenase (EC 1.1.1.1) activity le vels produced by the transfected genes indicates that multiple element s in both the 5' and 3' regions of the gene contribute to expression. The dispersed elements appear to function redundantly to ensure high l evels of expression. Moreover, in contrast to what has been reported f or other Drosophila Adh genes, some of the regulatory elements influen ce expression in both larvae and adults. In total, these results revea l a regulatory system in which the transcribed region is imbedded in a n extended genomic segment rich in cis-acting regulatory information. (C) 1998 Elsevier Science Ltd. All rights reserved.