Chromatin extrusion explains key features of loop and domain formation in wild-type and engineered genomes

ABSTRACT: We recently used in situ Hi-C to create kilobase-resolution 3D maps of mammalian genomes. Here, we combine these with new Hi-C, microscopy, and genome-editing experiments to study the physical structure of chromatin fibers, domains, and loops. We find that the observed contact domains are inconsistent with the equilibrium state for an ordinary condensed polymer. Combining Hi-C data and novel mathematical theorems, we show that contact domains are also not consistent with a fractal globule. Instead, we use physical simulations to study two models of genome folding. In one, intermonomer attraction during polymer condensation leads to formation of an anisotropic "tension globule." In the other, CTCF and cohesin act together to extrude loops during interphase. Both models are consist

ORGANISM(S): Homo sapiens

SUBMITTER: Suhas Rao 

PROVIDER: E-GEOD-74072 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress