Fig. 4a–b.

Quantitative super-resolution microscopy. a SMLM allows the stoichiometry of a molecule to be determined, with several over- or undercounting effects taken into account. (i) The photochemical properties of fluorescent proteins lead to specific blinking and bleaching behaviors. The high-blinking and fast-bleaching behaviors shown by mEos2 (left) and Dendra2 (right), respectively, are largely determined by the orientation of the single residue arginine 66. Reprinted with permission from [191]. (ii) Fluorophore blinking behavior can be corrected for using kinetic fluorophore schemes. In this strategy, the number of FliM proteins per flagellar motor is counted in vivo. Reprinted from [192]. (iii) Spatial organization of E. coli RNA polymerases under minimal as well as rich growth conditions. Reprinted with permission from [193]. (iv) Maturation of endocytic vesicles into late endosomes. Reprinted from [194]. (b) Structural super-resolution microscopy reveals the molecular architecture of cellular multicomponent complexes. (i) Mutual organization of various pre- and postsynaptic proteins in relation to the proteins Bassoon and Homer1. Reprinted with permission from [139]. (ii) Combining data from identical particles yields a high-resolution average. Systematic SMLM imaging of the Y-shaped subunit of the nuclear pore complex allows it to be aligned onto the electron density of the nuclear pore (bottom). Reprinted with permission from [104]. (iii) Aligning different pairs of synaptonemal proteins onto a helical template yields the three-dimensional model of the synaptonemal complex with isotropic resolution. Reprinted from [105]. Scale bars: a ii and a iii 500 nm; a iv 100 nm; b i 200 nm; b iii 2 μm