Two different virus-inducible elements are required for human beta-interferon gene regulation.

We show that the human beta-interferon gene promoter contains two different virus-inducible regulatory elements, PRDI and PRDII (positive regulatory domains I and II). A single copy of either element alone has no discernible transcriptional activity in mouse fibroblasts. However, multiple copies of either element function as a constitutive or virus-inducible transcription element depending on the cell line in which the sequence was tested. These results in conjunction with previous studies suggest that virus induction of the human beta-interferon gene is achieved through cooperative interactions between two entirely distinct virus-inducible elements. Comparison of the properties of these elements reveals that multiple copies of PRDI, but not PRDII, can be activated by three different inducers, beta-IFN, gamma-IFN and virus. These results suggest that the pathways of virus and interferon induction may share at least one common regulatory component.