RT Journal Article SR Electronic T1 Formation of Chromosomal Domains by Loop Extrusion JF bioRxiv FD Cold Spring Harbor Laboratory SP 024620 DO 10.1101/024620 A1 Fudenberg, Geoffrey A1 Imakaev, Maxim A1 Lu, Carolyn A1 Goloborodko, Anton A1 Abdennur, Nezar A1 Mirny, Leonid A. YR 2015 UL http://biorxiv.org/content/early/2015/08/14/024620.abstract AB Characterizing how the three-dimensional organization of eukaryotic interphase chromosomes modulates regulatory interactions is an important contemporary challenge. Here we propose an active process underlying the formation of chromosomal domains observed in Hi-C experiments. In this process, cis-acting factors extrude progressively larger loops, but stall at domain boundaries; this dynamically forms loops of various sizes within but not between domains. We studied this mechanism using a polymer model of the chromatin fiber subject to loop extrusion dynamics. We find that systems of dynamically extruded loops can produce domains as observed in Hi-C experiments. Our results demonstrate the plausibility of the loop extrusion mechanism, and posit potential roles of cohesin complexes as a loop-extruding factor, and CTCF as an impediment to loop extrusion at domain boundaries.