Individual activator and repressor transcription factors induce global changes in chromatin mobility

Abstract

The control of eukaryotic gene expression is intimately connected to highly dynamic chromatin structures. Gene regulation relies on activator and repressor transcription factors (TFs) that induce local chromatin opening and closing. Yet how nucleus-wide chromatin structures respond dynamically to the activity of specific TFs remains unclear. Here we asked how TFs with opposite effects on modulating local chromatin accessibility impact nucleus-wide chromatin dynamics in living cells. We combine High-resolution Diffusion mapping (Hi-D) and Dense Flow reConstruction and Correlation (DFCC) to obtain an imaging-based, nanometer-scale analysis of local diffusion processes and long-range coordinated movements of both chromatin and TFs in live cells. We show that expression of individual activator and repressor TFs increases nucleus-wide chromatin mobility and induces opposite coherent chromatin motions at the micron scale. Our quantitative analysis thus reveals the broad and differential impact of TFs opening and closing chromatin in nucleus-wide chromatin dynamics.