The objective of this award is to examine the relationship between chromatin structure and gene activity in higher eukaryotes. Studies on basal and regulated transcription by RNA polymerase II have generally focussed upon the identification and characterization of promoter-and enhancer-binding proteins with naked DNA templates. Recent findings on the mechanism of transcriptional activation by these sequence specific factors strongly suggest that dynamic interactions between chromatin and the transcription factors are involve in the regulation of gene expression. For instance, it has been found that these transcriptional "activators" may actually function as antirepressors--that is they appear, at least in part, to counteract repression of basal transcription by chromatin. In this award the working hypothesis is that there are key interactions between transcription factors and components of chromatin in the course of activation and repression of gene activity. Two different systems for reconstitution of chromatin will be developed, and then the resulting chromatin will be used as template for in vitro transcription analysis . These studies should lead to a better understanding of the process of gene activation and should eventually be applied to the molecular analysis of diseases involving improper expression of genes, such as some forms of cancer.
