Figure 3.

Temperature-induced volume transitions are sensitive to ionic conditions. (A) Deformation curves for HL60 nuclei in a 1064 nm OS at 23°C in 10 mM (black, n = 30), and 100 mM KCl (red, n = 42). (B) Deformation curves for HL60 nuclei in 0.1 mM (black, n = 46) and 1 mM MgCl₂ (red, n = 52). In both (A) and (B), the major deformation is denoted by the solid circles and the minor deformation by the open circles. (C) Phase diagram for TIVT in various salt conditions, depicting the transition to negative volume transitions in sufficiently high amounts of multivalent salts. (D) Volume changes of nuclei in salts of various valencies and concentrations as a function of initial nuclear volume. Temperature-induced swelling is sensitive to the valency and ionic radii of the salts. In all experiments, 1.7 W stretch power $\left(▵T_{\text{laser}}=18°\text{C}\right)$ was applied between t = 0 and 4 s. Volume changes were measured at t = 1 s into the stretch. n > 30 for each data point in (C) and (D). All error bars denote SE. To see this figure in color, go online.