Abstract
Proteins in nuclear extracts of HeLa cells that constitutively bound in vitro to three regions upstream of the interferon-inducible gene 6–16 were separated partially by chromatography on DEAE-Sepharose. Region one, a CCAAT box in the non-coding strand at position −63 to −67, was protected from DNase digestion by the bound protein(s) and was required for transcription in vitro. Region two, a tandem duplication sequence at position −89 to −168 contains two copies of a sequence essential for strong induction of the 6–16 gene by interferon in vivo. Region three, a palindromic sequence at position −449 to −465, not necessary for induction of 6-16 by interferon, was also protected from DNase digestion by nuclear protein(s). Templates with or without regions of two and three were transcribed equally well in extracts from interferon-treated or untreated cells.