Figure 9
Confocal microscopic images of suspended MT2 cells incubated with R.I.CK(fluorescein)-Tat9 (A-D) or PEG3.4 K-R.I.CK(fluorescein)-Tat9 (E-H) in the presence of endocytosis marker rhodamine-dextran at 37°C for 24 hours. A and E show fluorescein fluorescence (green), B and F are DIC images, C and G show rhodamine-dextran (red), and D and H show overlaying of the green and red images. Colocalization of two dyes (orange-yellowin the overlay images) implies endosomal uptake of PEG3.4 K-R.I.CK-Tat9. Cells incubated with R.I.CK(fluorescein)-Tat9 showed some faint green fluorescence that was not co-localized with the fluid phase endocytosis marker (arrows in Figure 9D), suggesting some cytosolic localization.