Distinction between AP1 and NF-E2 factor-binding at specific chromatin regions in mammalian cells

Specific nuclear factor-DNA complexes formed within the promoters and enhan cers are essential for transcriptional regulation, For eukaryotic systems, however, some DNA motif(s) are capable of binding to a family of related fa ctors, thus making it difficult to identify the factor actually binding on the chromatic DNA in vivo and modulating the local transcription processes, To resolve this matter, we have refined a chromatin immunoprecipitation as say. Using the assay, we could directly link the regulatory functions of ta o members of the AP1/NF-E2 transcription factor family and their stable bin ding in vivo within distinct chromatin regions, The study demonstrated the feasibility of a general scheme in the determination of the identity of spe cific factor(s), among a group of family members, bound at unique sequence( s) in living mammalian cells.