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.