Section: Application Domains

Light and electron microscopy for functional and structural analysis

In the post-genomic era, high resolution of protein structures becomes extremely important for accurate interpretations of biological functions at the molecular level. Meanwhile, microscopic imaging at both the light and electron microscopic levels provides unique multiscale information on protein localization and interactions. It extends and enriches data obtained from molecular and biochemical techniques. Recently, correlative microscopy has been designed and built to combine the advantages of light fluorescence microscopy with the high resolving power of electron microscopy [34] . Unfrotunately, there is probably no universal similarity measure for multimodal/multiscale image registration in light (LM) and electron (EM) microscopy. In this area, we investigate mutual information [44] and other statistical criteria to correlate intensities in EM and LM images. Data fusion and LM-EM image matching are challenging issues and correspond to a large variety of scales. It is worth noting that light microscopy images are relatively blurred when compared to EM images [42] . The definition of the space of transformations is also an open issue since rigid and non-rigid registration is required to compensate distortions and scale. By correlating different optical imaging methods (Photo Activation-LM, Structured Illumination-LM, PALM, FLIM-FRET) to the subcellular organization uniquely obtained by Electron Microscopy, we hope to overpass current knowledge on specific mechanisms involved in endosomal sorting, specialization and crosstalks between endosomes and these particular organelles.