RT Journal Article
SR Electronic
T1 CTCF and Cohesin Regulate Chromatin Loop Stability with Distinct Dynamics
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 093476
DO 10.1101/093476
A1 Anders S. Hansen
A1 Iryna Pustova
A1 Claudia Cattoglio
A1 Robert Tjian
A1 Xavier Darzacq
YR 2016
UL http://biorxiv.org/content/early/2016/12/13/093476.abstract
AB 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.