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bioRxiv · 10.1101/151563

Bridging the dynamics and organization of chromatin domains by mathematical modeling

Abstract

The genome is three-dimensionally organized in the cell, and the mammalian genome DNA is partitioned into submegabase-sized chromatin domains. Genome functions are regulated within and across the domains according to their organization, whereas the chromatin itself is highly dynamic. However, the details of such dynamic organization of chromatin domains in living cells remain unclear. To unify chromatin dynamics and organization, we recently demonstrated that structural information of chromatin domains in living human cells can be extracted from analyses of the subdiffusive nucleosome movement using mathematical modeling. Our mathematical analysis suggested that as the chromatin domain becomes smaller and more compact, nucleosome movement becomes increasingly restricted. Here, we show the implication of these results for bridging the gap between chromatin dynamics and organization, and provide physical insight into chromatin domains as efficient units to conduct genome functions in the thermal noisy environment of the cell.\n\nExtra View toShinkai S, Nozaki T, Maeshima K, Togashi Y. Dynamic Nucleosome Movement Provides Structural Information of Topological Chromatin Domains in Living Human Cells. PLoS Comput Biol. 2016;12(10):e1005136. doi: 10.1371/journal.pcbi.1005136. PubMed PMID: 27764097; PubMed Central PMCID: PMCPMC5072619.\n\nFundingThis work was supported by Platform Project for Supporting in Drug Discovery and Life Science Research (Platform for Dynamic Approaches to Living System) from MEXT and AMED; KAKENHI under Grant JP16H01408, JP23115007, JP23115005, JP16H04746; CREST grant (JPMJCR15G2) from JST; and Research Fellowship for Young Scientists under Grant JP13J04821, JP16J07205.\n\nDisclosureNo potential conflicts of interest were disclosed.\n\nAcknowledgementsWe would like to thank Dr. Takashi Toda for comments regarding the manuscript.

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Shinkai, S., Nozaki, T., Maeshima, K., Togashi, Y.. 2017-06-18. Bridging the dynamics and organization of chromatin domains by mathematical modeling. https://doi.org/10.1101/151563

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