The putative promoter element is A-form and binds ilf3 in vitro . (a) Duplex 36 bp oligonucleotides corresponding to the five identified putative promoter elements display A-form DNA characteristics as observed by circular dichroism. (b) These duplex oligonucletides are shifted in EMSA experiments, these complexes are competed by titration of unlabelled self-competitor but not by CCAAT box containing B-form duplexes. The specific complexes are indicated by arrows. (c) The sequence of the B-form competitor used in the EMSA is shown, the CCAAT box is indicated in bold.