A NOVEL TRANSCRIPTION FACTOR AND 2 MEMBERS OF THE SP1 MULTIGENE FAMILY REGULATE THE ACTIVITY OF THE ALPHA-2(VI) COLLAGEN PROMOTER

For a better understanding of the processes that lead to the activatio n or inhibition of type VI collagen synthesis, we have identified and characterized the cis-acting elements of the chicken alpha 2(VI) colla gen promoter. This promoter encompasses four sites, termed S1, S2, X a nd S3, which interact with nuclear factors. Sites S1, S2 and S3 are ea ch recognized by the same two proteins that belong to the Spl multigen e family. Site X appears to interact with a novel transcription factor of 43 kDa. When a fragment containing all four of the elements is pla ced in front of a reporter gene, the resulting construct is able to in duce a high level of transcription in chicken fibroblasts. As soon as a single element is deleted from this construct, the activity decrease s drastically. Thus, the four elements are essential for the transcrip tional activation of the ct 2 (VI) collagen gene.