TY - JOUR T1 - CTCF and Cohesin Regulate Chromatin Loop Stability with Distinct Dynamics JF - bioRxiv DO - 10.1101/093476 SP - 093476 AU - Anders S. Hansen AU - Iryna Pustova AU - Claudia Cattoglio AU - Robert Tjian AU - Xavier Darzacq Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/12/13/093476.abstract N2 - Folding of mammalian genomes into spatial domains is critical for gene regulation. CTCF and cohesin control domain location by folding domains into loop structures, which are thought to be highly stable. Combining genomic, biochemical and single-molecule imaging approaches, we show that although CTCF and cohesin can physically interact, CTCF binds chromatin much more dynamically than cohesin (~1 min vs. ~22 min residence time). Moreover, after unbinding, CTCF quickly rebinds another cognate site unlike cohesin (~1 min vs. ~33 min). Thus, CTCF and cohesin form a rapidly exchanging “dynamic complex” rather than a typical stable complex. Since CTCF and cohesin are required for loop domain formation, our results suggest that chromatin loops constantly break and reform throughout the cell cycle. ER -