TRANSCRIPTION FACTOR-INDUCED, PHASED BENDING OF THE E-SELECTIN PROMOTER

E-selectin is an endothelial adhesion molecule that is critically invo lved in neutrophil adhesion and recruitment. All DNA elements required for interleukin-l inducibility have been located in the proximal prom oter: an NF-ELAM1/ATF site, two NF-kappa B sites (I and II), the NF-EL AM2 element and a TATA box We show here that interleukin-1 induced pro moter activity is exquisitely sensitive to the spatial arrangements of these elements. Phasing of the ATF and NF-kappa B II elements indicat es that their relative helix orientation is more important than distan ce per se. This sensitivity is partly due to a requirement for correct ly oriented, transcription factor-induced DNA-bending. (i) Band shift analyses with permuted ATF- and NF-kappa B elements show that their as sociated factors all bend DNA (ii) One can functionally replace the NF -ELAM1/ATF element by a subset of a panel of DNA fragments that contai n defined bends in various planes, We conclude that the main role of t he factors binding at the NF-ELAM1/ATF element is to alter the conform ation of the E-selectin promoter, presumably looping distant enhancer elements into each other's proximity,