How are chromosomes organized in the nucleus?
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Chromosomes are organized in the nucleus through various mechanisms. One mechanism is the tethering of specific loci to nuclear landmarks, which leads to massive reorganization of the nucleus . Another mechanism is the spatial compartmentalization of chromatin, driven by molecular affinities, resulting in the spatial isolation of active and inactive chromatin . Additionally, loop extrusion activity of SMC complexes plays a role in interphase chromatin folding and mitosis . Epigenetic modifications, allosterically regulated transcription factors, and a nucleoskeleton system comprised of actin, myosin, and actin-binding proteins also contribute to chromosome folding and positioning . High-throughput chromosome conformation capture techniques have revealed that chromosomes are folded in multiple high-order structures, including Topologically Associating Domains (TADs) and active/repressive compartments . Furthermore, cryo-electron tomography has shown a large-scale interphase chromosome structure that coils the nucleosome 11-nm fiber into a defined hollow structure, which can be used to explain chromosome territories and other chromosome architectures .
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| The paper discusses the organization of chromosomes in mammalian interphase nuclei into domains called chromosome territories. | |
| The paper discusses how chromosomes are organized within the nucleus, specifically focusing on the discovery of higher-order chromosomal structures such as Topologically Associating Domains (TADs) and their role in genome function. | |
37 Citations | The paper discusses three key mechanisms of chromosome organization in the nucleus: tethering of specific loci to nuclear landmarks, spatial compartmentalization of chromatin, and loop extrusion activity of SMC complexes. |
4 Citations | The paper discusses the cellular mechanisms involved in chromosome folding and positioning within the nucleus, including the use of epigenetic modifications, transcription factors, and a nucleoskeleton system. However, it does not provide specific details on how chromosomes are organized in the nucleus. |
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