Multiple transcription factors interact with the adenovirus-2 EII-late promoter: evidence for a novel CCAAT...

Multiple cellular transcription factors have been shown to interact with the upstream region of the adenovirus-2 EIIa-late promoter. One of these factors recognises each of the three CCAAT motifs present in the EIIL promoter at positions -72, -135 and -229, as well as the CCAAT elements in the rat albumin and herpes virus thymidine kinase promoters. A mutation known to reduce thymidine kinase promoter activity in vivo and in vitro abolishes binding of the factor, termed CCAAT recognition factor (CRF), which appears to be distinct from previously identified CCAAT factors. In addition, another protein, termed upstream factor II (USFII), shares binding sites at position -110 in the EIIL promoter and in the c-fos enhancer adjacent to the serum regulatable element. The recognition site for USFII is also found in the c-fos promoter and in the adenovirus early region EIV and EIIa-early promoters. An Sp1 recognition site has also been identified at position -41, and the binding sites for Sp1, USFII and CRF are all required for efficient EIIa-late promoter function. Finally, an additional factor recognising the consensus GGGGGGNT has been detected.