Figure 2.

The six base pairs upstream of the TATA box define polarity of transcription. (a) Diagram of plasmid constructs based on pINIT with derivatives of the ef1α promoter in which the six nucleotides found upstream (pUP-INV) or downstream (pDO-INV) of the TATA box in the natural ef1α promoter are present as inverted repeats flanking the TATA box. (b) In vitro transcription assays using pUP-INV and pDO-INV. Transcription products were detected by using the T3 or T7 sequencing primers. (c) EMSAs using TFB and TBP on double-stranded oligonucleotides corresponding to the pUP-INV or pDO-INV TATA box and flanking sequences.