We have analyzed the 5'-flanking regions of the Drosophila genes encoding t
he TFIIB and TATA box-binding proteins (TBP) and mapped the regulatory regi
ons required for their efficient expression. We found that the 500 bp long
region (-439 to +60) and the 401 bp long region (-261 to +138) are required
for the efficient expression of TFIIB and TBP genes, respectively. In the
TFIIB promoter region, the upstream DNA between -439 and -280 and the downs
tream DNA between +8 and +60 are necessary for the stimulation of promoter
activity. The upstream DNA between -439 and -280 stimulates transcription i
n an orientation dependent manner. In the TBP promoter region, the upstream
DNA between -261 and -207, and the downstream DNA between +15 and +138 are
necessary for the stimulation of promoter activity. The upstream DNA (-261
to -207) required for TBP promoter activity contains a 11 bp long palindro
mic sequence and a DNA replication-related element sequence. Particularly,
we could find that the downstream promoter regions of TFIIB and TBP genes c
ontain the conserved nucleotide sequences, suggesting the presence of a com
mon regulatory mechanism for the expression of these two genes.