Fig. 2

Cell-cycle-dependent macropinocytosis and expression of Tat/pDNA-Ca²⁺ nanoparticles. Confocal imaging the uptake of Tat/pGL3-Ca²⁺-DiYO1 nanoparticles mixed with Dextran-RD in Skov3 and Cos7 cells: (A) uptake for different time, (B) uptake in cell-cycle of I- (polygons with thin dotted line) and M-phases (polygons with bold solid line), (F) uptake in sub-phases of cell-cycle (Cos7, 4 h). Cell nuclei were stained with Hoest33342. Scale bar: 10 μm. (C, D, G, H) Scatterplots depict the uptake level of particles in the indicated cell population. 60 cells were counted for any sub-phase in each experiment. (E) Sub-phase-arrested cells were induced by drug treatments as described in ‘Materials and Methods’. (I, J) Uptake level of Dextran-RD and Tat/pGL3-Ca²⁺-DiYO1 in sub-phase-arrested Skov3 cells was quantified by fluorescence microplate reader. RFUs/mg protein: relative fluorescence intensities per milligram protein. (K, L) Luciferase activity of sub-phase-arrested cells transduced with Tat/pGL3-Ca²⁺ nanoparticles for 4 and 14 h, respectively. RLUs/mg protein: relative light units of expressed luciferase per milligram. n = 3. Statistically significant differences in relation to control (no drug treatment) are shown: **P < 0.01, *P < 0.05