UC San Diego

The transcription machinery requires spatiotemporal coordination of its regulatory elements for precise gene expression. It is believed that the dynamics in the nuclear architecture like enhancer:promoter looping interaction is essential for the regulation of the transcription machinery. However, the detail of the change in 4D nuclear architecture during transcription is poorly understood. Here we seek to visualize a pair of enhancer and its associated target gene based on a real time, live cell imaging that uses optimized CRISPR-Cas9 and MS2/PP7 system. Our prior work on measuring TFF1 transcription bursting in MCF7 cells confirmed the efficiency and sensitivity of our imaging techniques. In this study, we aim to visualize c-MYC enhancer(c-MYCe) and c-MYC gene in live HeLa cells based on our preliminary data proving that c-MYC enhancer is a functional enhancer. We plan to measure the relative timing of signal, the duration of activity, and the distribution of intensity over the course of activity. The spatial kinetics between c-MYCe and c-MYC over time will be measured, and their motion relative to transcriptional activity (on/off signal) will be examined. Collectively, we hope to advance the understanding of the precise 4D dynamics of the events underlying enhancer-mediated transcription regulation.