Mitotic Chromosome Mechanics: How Cells Segregate Their Genome Paul Batty, Daniel W. Gerlich  Trends in Cell Biology  DOI: 10.1016/j.tcb.2019.05.007 Copyright © 2019 The Authors Terms and Conditions

Figure 1 Overview of Chromosome Reorganisation during Cell Cycle Progression. (A) Illustration of chromosomal DNA (red) topology. (B) Binding to and dissociation from chromosomes of key molecular factors discussed in this review [condensin I, condensin II, cohesin, Ki-67, and BAF (barrier-to-autointegration factor)]. Bars indicate timelines corresponding to the cell cycle stages illustrated in (A). Colours indicate relative changes in abundance on chromosomes during cell cycle progression, with dark blue representing highest abundance. Trends in Cell Biology DOI: (10.1016/j.tcb.2019.05.007) Copyright © 2019 The Authors Terms and Conditions

Figure 2 Models for Mitotic Chromosome Assembly in Vertebrate Cells. Schematics illustrate cross sections of a chromatid. (A) During prophase, condensin II extrudes DNA loops to form a cylindrical structure with condensin II enriching at the chromosome axis. (B) Following nuclear envelope disassembly, condensin I extrudes smaller DNA loops nested within loops formed by condensin II. (C) Throughout prophase, weak and transient interactions between nucleosomes mediate global compaction of chromatin. (D) During late prophase, Ki-67 forms a molecular brushlike structure on the surface of chromatin, contributing to maintenance of separate chromosome bodies. Broken lines indicate regions of interest displayed in subpanels. For details see main text. Trends in Cell Biology DOI: (10.1016/j.tcb.2019.05.007) Copyright © 2019 The Authors Terms and Conditions

Figure 3 Chromosome Surface Regulation during Nuclear Assembly. (A) During early anaphase, BAF (barrier-to-autointegration factor) is phosphorylated on its DNA binding domains and therefore localises to the cytoplasm. (B) During mid-anaphase, dephosphorylation of BAF results in the formation of a dense chromatin network at the surface surrounding each set of anaphase chromatids. (C) During late anaphase, the BAF-chromatin network restricts membranes of the reassembling nuclear envelope to the surface surrounding the entire set of chromosomes, thereby shaping a single nucleus. Reproduced, with permission, from [88]. Trends in Cell Biology DOI: (10.1016/j.tcb.2019.05.007) Copyright © 2019 The Authors Terms and Conditions