Curved DNA and Prokaryotic Promoters

Abstract

Intrinsically curved DNA structures often occur in or around origins of DNA replication, regions that regulate transcription, and DNA recombination loci, and are found in a wide variety of cellular and viral genomes from bacteria to man. In bacterial promoters, bent DNA structures are often located from immediately upstream of the ?35 hexamer to around position ?100 relative to the transcription start site (+1). They have a range of functions: facilitating RNA polymerase binding to the promoter, transition from closed to open promoter complexes, or transcription factor binding. To perform these functions, in some cases intrinsically curved structures function together with DNA bends that are induced by binding of RNA polymerase, transcription factors, or nucleoid-associated proteins. This chapter will describe how curved DNA structures are implicated in prokaryotic transcription.