Detection of factors that interact with the human beta-interferon regulatory region in vivo by DNAase I footprinting.

We have used a DNAase I genomic footprinting procedure to detect interactions between cellular factors and the regulatory sequences of the human beta-interferon gene. Prior to induction with poly(I)-poly(C), factors that bind to DNA are detected in one region located between -94 and -167 from the mRNA cap site, and in another region located between -68 and -38. After induction these factors dissociate and another factor binds to a region located between -77 and -64. Correlation of these footprints with the effects of deletions in the regulatory region of the beta-interferon gene (accompanying paper) suggest that the factors that bind prior to induction are repressor molecules, while the component that binds after induction is a transcription factor. Dissociation of the repressor molecules from the DNA after induction may allow the transcription factor to bind to and activate the beta-interferon promoter. Thus, the beta-interferon gene may be controlled by a negative regulatory mechanism.