FCS and Sub-diffraction Resolution Fluorescence Imaging of Membrane Receptors in Living Organelles

Abstract

Fluorescence microscopy is a standard tool in molecular biophysics, but even the best resolution obtained by diffraction-limited conventional optical techniques misses the molecular level by two orders of magnitude. In order to overcome the classical diffraction limit, several sub-diffraction resolution imaging methods have been introduced so far. Direct stochastic optical reconstruction microscopy (dSTORM) (1) and PAINT (points accumulation for imaging in nanoscale topography) (2) have the potential to shed light on the intracellular organization of cells with near-molecular resolution. These techniques will be used to localize labelled peptides binding to receptors located in the membrane of protoplasts of the flowering plant Arabidopsis (a model organism for plant research). Binding dynamics will be studied by fluorescence correlation spectroscopy (FCS).