Abstract
Current attention in transcriptional regulation is focused on the properties of coactivators and corepressors that mediate communication between sequence-specific transcription factors, the basal transcriptional machinery and the chromatin environment. Nuclear and steroid hormone receptors represent the best-understood transcription factors that utilize coactivators and corepressors. This review considers the access of these receptors to chromatin, the modifications of chromatin structure that the receptors instigate and the implications for transcriptional control. Nucleosome positioning and targeted histone modification emerge as central controlling elements for gene expression.