Breaking the Diffraction Barrier: Super-Resolution Imaging of Cells Edgar Ferrer-Lorenzo, Nicole Gagnon, Anna Torre 1

Optical microscopes have limitations Diffraction limited Resolution depends on the wavelength of light and diameter of lens of optical microscope Specimen not alive The solution: STORM 2

STORM fluorescence microscopy can overcome the diffraction limit A StORM image is constructed from the localization of individual fluorescent molecules that are switched on and off using light of different colors 3

STORM’s method improves the resolution of fluorescence microscopy 4

STORM provides sub-diffraction- limit image resolution Rust et al., Nature Methods 3: (2006). Betzig et al., Science 313: (2006). 5

Creating an image with STORM 6 Huang et al., Cell 143: (2010).

Applications of STORM Cell biology Microbiology Neurobiology 7

STORM can resolve DNA structure Fluorophores bound to DNA fragment RecA coated circular plasmid DNA Rust et al., Nature Methods 3: (2006). 8

High resolution images of microtubules Bates et al., Science 317, (2007). 9

STORM can resolve 3D structure Bates et al., Science 317, (2007). 10

High resolution imaging of the action cytoskeletal network in neurons Xu et al., Science 339: (2013). 11

STORM has advanced biology Unambiguous identification of specific proteins Protein-protein interactions Structure of small-type protein complexes Live cell dynamics Single molecule tracking Cluster analysis and molecular counting 12

Conclusions 1.STORM has found a clever way to get around the diffraction limit of resolution 2.Imaging resolution down to 20 nm 3.High-resolution live-cell imaging, thus enabling discovery of internal causes or origins of processes 4.All with visible light! 5.Imaging speed can be improved 13