Fast high-resolution 3D total internal reflection fluorescence microscopy by incidence angle scanning and azimuthal averaging

Significance
Recent progress has pushed forward the resolving capacity of optical microscopy at the expense of a low acquisition rate and use of specific probes. Such limitations make these techniques incompatible with dynamics localization of multiple elements in single cell. We report here a method to recover 3D volumes from images obtained using several total internal reflection fluorescence (TIRF) incidence angles at dense regime of acquisition. This approach allows investigating several dynamical processes occurring in depth of the cell up to 800 nm from the plasma membrane such as actin remodeling. The study of time-correlated molecular behaviors at the very late steps of vesicle docking–fusion during exocytosis of two distinct recycling transport intermediates, in 3D and at high axial resolution, is also accessible.