Fig. 3: Osmotic, mechanical, and active transport contribute to nucleus-cytoplasm volumetric coupling determination.

Dynamic perturbations: a–e hyperosmotic shock, f–j detachment and k–o spreading. Representative cell and cytoplasmic height evolution of a RPE1 cell during hyperosmotic shock (b), detachment (g) and spreading (l) experiments. Scale bar is 20 µm. Mean (±SE) normalized nuclear and cytoplasmic volume trajectories during hyperosmotic shock (n = 24) (c), detachment (n = 23) (h) and spreading (m). In (c), the red vertical line represents the osmotic shock time point. In (m), the continuous line is relative to untreated cells (n = 47) while the dashed line is to ivermectin ones (n = 22). Mean (±SE) normalized NC ratio trajectories during hyperosmotic shock (d), detachment (i) and spreading (n). In (d), the red vertical line represents the osmotic shock time point. In (n), the dashed line is relative to ivermectin-treated cells, while the continuous line to untreated cells. Mean (±SE) normalized inverted FRET index value during hyperosmotic shock (n = 20) (e), detachment (n = 10) (j) and spreading (o). In (e), the red vertical line represents the osmotic shock time point. In (o), the dashed line is relative to ivermectin-treated cells (n = 10), while the continuous line to untreated cells (n = 14). Difference in normalized volumetric NC ratio was tested with a two-tailed paired t-test, p values: 0.08 (d), 4.05·e⁻⁸ (i), 3.14·e⁻⁶ (N, ctrl), 0.0005 (N, iver). Difference in normalized iFRET index was tested with a two-tailed paired t test, p values: 0.0016 (e), 0.0012 (j), 3.76·e⁻⁵ (o, ctrl), 6.31·e⁻⁷ (o, iver). Source data are provided as a Source Data file. “n” represents the number of cells examined over at least three independent experiments.