Interferon response element of the human gene 6‐16.

1046 base‐pairs (bp) of genomic DNA spanning the first exon of the human alpha/beta‐interferon (IFN)‐inducible gene 6‐16 have been analysed for their role in induction. The whole gene or 5′‐flanking deletion derivatives of it were assayed for inducibility in populations of stably transfected mouse cells. 5′‐Flanking DNA fragments were assayed for their ability to confer inducibility on a reporter gene in stably and transiently transfected mouse and human cells. The data suggest that a 39 bp sequence is sufficient to confer transcriptional inducibility and can account in large part for the response of 6‐16. Two copies of this sequence, one of which contains a dinucleotide insert, are located in tandem 88 bp upstream of the 6‐16 transcriptional initiation site. For at least one of the repeat units the 5′ limit of a subregion required for induction lies in the sequence GGGAAAAT. The motif GGAAA occurs in several well characterized enhancers. Furthermore, one residue 3′ of the GGAAA there is a second motif, TGAAACT, which is conserved in the regulatory regions of other IFN‐induced genes. In gel retardation assays the oligonucleotide GGGAAAATGAAACT competes with the repeat element for binding to IFN‐modulated protein(s) but a mutated oligonucleotide, GGGAAAATGACACT does not. These results identify an alpha/beta IFN response element partially homologous to those described previously for the genes of the MHC complexes.