NPCs are actively delivered to the daughter NE during mitosis. (A) Anaphase progression of cells producing Nup188-GFP and Sur4-mCherry was followed using epifluorescence microscopy. Images were acquired at 4-min intervals. 0 min was defined as the moment the fluorescing protein entered the daughter. Bar, 5 µm. (B) The daughter-specific signal intensity of the indicated fluorescent protein was quantified at each time point (n = 13). The fluorescence intensities within the daughter cell during anaphase were normalized as follows: signal levels in the daughter cell before entry of the NE (t < 0 min) were set at 0, and those after entry into telophase (t ≥ 20 min) at 1. Error bars represent standard deviation. (C) Anaphase cells producing Nup188-GFP or Sur4-GFP were analyzed by FRAP. Daughter (D) or both daughter and mother (D+M) cell signals were bleached and fluorescence recovery was monitored using confocal microscopy at 20-s intervals. Each image was derived from a summed projection of a z-stack series. Bar, 5 µm. (D) Plots of integrated fluorescent intensities of Nup188-GFP and Sur4-GFP in the daughter cell (n = 8–10) at various time points after photobleaching. Minimal Nup188-GFP recovery gave a straight-line plot (circles), whereas Sur4-GFP recovered with relaxation kinetics (squares) and a rate constant of 1.09 ± 0.03 × 10−2 s−1. Error bars represent standard deviation.
