Helical coiled nucleosome chromosome architectures during cell cycle progression

• 成果类型: Article
• 署名作者: McDonald, Angus; Murre, Cornelis; Sedat, John W.
• 署名单位: Boise State University; University of California System; University of California San Diego; University of California System; University of California San Francisco
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12057
• DOI: 10.1073/pnas.2410584121
• 发表日期: 2024-10-22
• 关键词: melanogaster interphase nuclei; spatial-organization; 3-dimensional organization; functional-organization; polytene chromosomes; drosophila; dna; tomography

摘要

Recent studies showed an interphase chromosome architecture-a specific coiled nucleosome structure-derived from cryopreserved EM tomograms, and dispersed throughout the nucleus. The images were computationally processed to fill in the missing wedges of data caused by incomplete tomographic tilts. The resulting structures increased z- resolution enabling an extension of the proposed architecture to that of mitotic chromosomes. Here, we provide additional insights into the chromosome architecture that was recently published [M. Elbaum et al., Proc. Natl. Acad. Sci. U.S.A. 119, e2119101119 (2022)]. We build on the defined chromosomes time- dependent structures in an effort to probe their dynamics. Variants of the coiled chromosome structures, possibly further defining specific regions, are discussed. We propose, based on generalized specific uncoiling of mitotic chromosomes in telophase, large- scale reorganization of interphase chromosomes. Chromosome territories, organized as micron- sized small patches, are constructed, satisfying complex volume considerations. Finally, we unveiled the structures of replicated coiled chromosomes, still attached to centromeres, as part of chromosome architecture.