Activation of the adenovirus EIIa late promoter by a single-point mutation which enhances binding of transcription factor IID.

We have converted the TACAAA sequence present at position -29 of the adenovirus EIIa late promoter into a canonical TATA box by oligonucleotide-directed mutagenesis. When linear templates were analyzed in nuclear extracts, transcription of the mutant promoter showed a 10-fold higher level of activity than that of the wild-type promoter. This increase was correlated with an increased affinity of the mutant promoter for transcription initiation factor IID. Further analyses demonstrated that the activating functions of three EIIa late upstream promoter elements (Huang, D.-H., and Roeder, R.G. (1988) Mol. Cell. Biol. 8, 1906-1914) were maintained in the mutant promoter background. These observations indicated, first, that the upstream elements did not act merely to overcome a rate-limiting initiation step imposed by an inefficient TATA element and, second, that the strength of the interaction between transcription initiation factor IID and the TATA box was directly related to promoter activity.