BSC1 (monkey kidney epithelial) cells stably expressing rat brain clathrin light chain-EGFP (kindly provided by T. Kirchhausen, Harvard Medical School, Boston, MA) were cultured and prepared as specified in Supplementary Note 13 online. For live cell imaging, BSC1 cells were plated on glass coverslips, and through-the-objective TIR-FM was performed on a Nikon TE2000U inverted microscope using a 100X/1.45NA oil-immersion objective. Images were captured at 0.5 Hz with 200ms exposure time using a Hamamatsu Orca II-ERG.