Fig. 3: Nucleosomes are increasingly more constrained during the chromosome assembly process.
a Fluorescent images of FA-fixed HCT116 cells in different cell cycle stages. From left to right: G2, prophase, prometaphase, metaphase, anaphase, and telophase. DNA was stained with DAPI. b MSD plot (±SD among cells) of nucleosomes during the chromosome assembly process of HCT116 cells. Cells were released from G2, which had been arrested with RO-3306107. Nucleosomes in G2, prophase, prometaphase, metaphase, anaphase, and telophase were monitored. MSD plot (±SD among cells) of TMR-labeled nucleosomes in living HCT116 cells in G2 (black, n = 22 cells), prophase (pale blue, n = 13 cells), prometaphase (pale purple, n = 23 cells), metaphase (pale magenta, n = 17 cells), anaphase (magenta, n = 16 cells), and telophase (blue, n = 14 cells) from 0.05 to 0.5 s. The Kolmogorov-Smirnov test (two-sided) was used to determine P values. ***, P ≤ 0.0005 for G2 phase versus metaphase (P = 2.1 × 10−4), G2 phase versus anaphase (P = 7.0 × 10−6), and G2 phase versus telophase (P = 2.2 × 10−4). MSD exponents from Supplementary Fig. 2c and asymmetry coefficient (AC) values from Supplementary Fig. 2d are also shown in the brackets. c MSD values at 0.5 sec in each cell stage from Fig. 3b were plotted with distributions. Whiskers and bounds of boxes show maxima, minima, and first/third quantiles. Gray and black bars show their mean and median values, respectively. Note that nucleosomes are increasingly more constrained with the progression of chromosome assembly. The Kolmogorov-Smirnov test is described in Fig. 3b.
