Sp1 interacts with the consensus sequence for Egr-1 gene product with a cellular factor(s) and activates the transcription through this element.

We report that Sp1 from nuclear extracts of BRL-3A cells interacts with the consensus DNA sequence for the Egr-1 gene product in an overlapping manner. Purified Sp1 failed to bind to this sequence and with the addition of sub-saturating level of nuclear extracts, the binding activity appeared. In Drosophila cells (SL2), exogenously expressed Sp1 activated the transcription through the Egr-1 site. These findings suggest that Sp1 can be targeted to a non-Sp1 (Egr-1) site with a cellular factor(s) and can activate the transcription through this element.