[초청강연] A probabilistic model of inter-chromosomal interactions mediated by cell type-common super-enhancers

Inter-chromosomal interactions have emerged as a substantial part of genome organization and
various biological processes. However, the organizational principles of inter-chromosomal interactions
remain to be elusive. Here, we develop a new computational method to systematically probe inter-
chromosomal interactions using in situ Hi-C results from various cell types. The new method
recapitulates two distinct hub-like inter-chromosomal contacts associated with nuclear speckles and
nucleoli, respectively. Interestingly, nuclear speckle-associated inter-chromosomal interactions are
highly cell-type invariant with a striking enrichment of cell-type common super-enhancers (CSEs).
Validation using DNA Oligopaint FISH reveals strong but stochastic interaction behaviors between
nuclear speckles and genomic regions harboring CSEs, in contrast to the results from a fixed hub-like
structure. Based on our results, we propose a model that explains the likelihood of speckle-associated
inter-chromosomal contacts, which accurately predicts the inter-chromosomal contacts observed from
both Hi-C and DNA Oligopaint FISH. These results highlight the probabilistic nature of establishing
inter-chromosomal interactions and underlying principles.