Figure 6.

Cryptogein-stimulated endocytosis does not occur in cells inhibiting ROS production. The morphology of gp3 cells (antisense line of NADPH oxidase NtrbohD), which no longer produce ROS, was imaged by TEM. CCPs (arrows) were observed and quantified. A, Micrographs of three representative cell sections showing flat pits delimited at the intracellular face by a clathrin electron-dense coating (arrows). Bars = 100 nm. B, Relative increase of CCPs in gp3 cells in the absence or presence of 50 nm cryptogein; cell sections presenting no CCP (class 0), one CCP (class 1), or two or more CCP (class 2) within a 100-μm membrane perimeter (n = 20–30). C, Distribution of CCPs according to their shape in elicited (cry) or nonelicited (ctl) wild-type and gp3 cells after 15 min. Three classes of CCP were defined as a function of their diameter: flat (90–120 nm), curved (70–90 nm), and invaginated (40–70 nm). n = 20 to 30 cell sections.