Identification of a novel virus-responsive sequence in the promoter of murine interferon-alpha genes.

We have previously shown that the infection of mouse L-cells with Newcastle disease virus activates transcription of the alpha 4 but not the alpha 6 interferon gene and that the induction is mediated by a 35-base pair inducible element (IE) found in the alpha 4 promoter (-109 to -75). In the present study, we show that the inactivity of the alpha 6 promoter can be mapped to 2 out of 6 nucleotides in which the alpha 6 differs from alpha 4 IE. The symmetrical sequence, GTAAAGAAAGT (-103 to -93), present in the alpha 4 IE is essential for its inducibility and binding of nuclear protein(s) to the alpha 4 IE.