Abstract

Studies of transcriptional control sequences responsible for regulated and basal‐level RNA synthesis from promoters of Drosophila melanogaster retrotransposons reveal novel aspects of gene regulation and lead to identification of trans‐acting factors that can be involved in RNA polymerase II transcription not only of retrotransposons, but of many other cellular genes. Comparisons between promoters of retrotransposons and some other Drosophila genes demonstrate that there is a greater variety in basal promoter structure than previously thought and that many promoters may contain essential sequences downstream from the RNA start site.