Triple colocalization experiments with H3-targeted polyplexes, importin-4, and Rab6, or H3-targeted polyplexes, importin-4 and Sec61. (a) Representative confocal z-stack slice of H3-targeted polyplexes (red), nucleus (blue), Rab6 (green), and importin-4 (magenta). (b) Representative confocal z-stack slice of H3-targeted polyplexes (red), nucleus (blue), Sec61 (green), and importin-4 (magenta). Arrows represent points of triple colocalization. The scale bar (shown in a) = 10 μm. (c) Quantification of colocalization with H3-targeted polyplexes, importin-4, and Rab6 (black); H3-targeted polyplexes, importin-4, and Sec61 (dark gray); or importin-4 and Sec61 alone (light gray). * Indicates a statistically significant difference between the previous time point for a given sample (P < 0.05).