Direct Visualization of Transcription Factor-Induced Chromatin Remodeling and Cofactor Recruitment In Vivo

Abstract

Publisher Summary This chapter presents the assays for chromatin remodeling, transcription factor, and coactivator recruitment based on direct, microscopic observations within individual live cells. The experimental basis for this approach involves the visualization of chromosome regions containing multiple transgene copies. To show this, two approaches have been used in the chapter. The first uses direct repeats of bacterial operators to bind repressor fusion proteins as a means of tethering specific transcription factors to specific chromosomal sites. The second uses repeats of transgenes containing viral promoters with binding sites for known transcription factors. It is anticipated that a natural experimental progression will be to combine both of these approaches, using the bacterial operator repeats for tagging the chromosome regions, while using transgene repeats containing specific promoters with known transcription factor-binding sites and reporter constructs for monitoring gene expression. These methods allow real-time visualization of transcription factor dynamics and their relationship to changes in chromatin structure and gene expression.