Chemically inducible internalization: comparison of clathrin hooks. (A) Comparison of four potential clathrin hooks for chemically inducible endocytosis. Cells expressed CD8–mCherry–FRB with FKBP–β1–GFP, FKBP–α–GFP, FKBP–epsin–GFP, or FKBP–β3–GFP. Stills from live-cell confocal imaging experiments are shown: (left) image shows the frame before rerouting occurs and (right) 133 frames (665 s) later. Inset shows a 2× zoom of the boxed region. Bars: (main) 10 µm; (insets) 2 µm. (B) Mean plots to show chemically inducible endocytosis. Colored traces indicate the total area of bright GFP puncta that form in cells after rerouting. Traces were time aligned and averaged. (C) Scatterplot to indicate variability in chemically induced endocytosis. The total normalized area above threshold at 5 min after rerouting for each cell analyzed is shown (spots). ANOVA, P = 1.142 × 10−5. Bars indicate mean ± SD. Number of cells = 8–15 and number of experiments = 3.
