Mammalian genes are regulated by enhancers, which can be hundreds of kilobases to megabases away from the gene whose expression they control by forming chromatin loops. Understanding mammalian gene regulation therefore requires understanding 3D genome organization. We have developed new chemical biology, computational and biophysical approaches to visualize the key proteins, CTCF and cohesin, that control chromatin looping at single-molecule resolution inside living cells. Similarly, we have developed approaches to directly visualize chromatin loops and to follow them dynamically as they form, function, and break inside living cells. We will discuss our results from these studies, which suggest that 3D genome organization and chromatin loops are likely much more dynamic than previously anticipated.
Anders Hansen, PhD (UC Berkeley)