The DNA replication-related element (DRE)-DRE-binding factor (DREF) systemmay be involved in the expression of the Drosophila melanogaster TBP gene

The TATA box binding protein (TBP) is a general transcription factor requir ed for initiation by all three eukaryotic RNA polymerases. Previously, we f ound that the promoter region of the Drosophila melanogaster TBP gene conta ins three sequences similar to the DNA replication-related element (DRE) (5 '-TATCGATA). In the present study, we found that the DRE-like sequences are also present in the promoter of the Drosophila virilis TBP gene, suggestin g a role for these sequences in TBP expression, Band mobility shift assays revealed that oligonucleotides containing sequences similar to the DRE of D . melanogaster TBP gene promoter form specific complexes with a factor in a Kc cell nuclear extract and with recombinant DRE-binding factor (DREF). Fu rthermore, these complexes mere either supershifted or diminished by monocl onal antibodies to DREF. Transient luciferase assays demonstrated that indu ction of mutations in two DRE-related sequences at positions -223 and -63 r esulted in an extensive reduction of promoter activity. Thus, the DRE-DREF system appears to be involved in the expression of the D. melanogaster TBP gene. (C) 2000 Federation of European Biochemical Societies. Published by E lsevier Science B.V. All rights reserved.