Advanced microcopy to study tracking and spatiotemporal organization of intracellular membranes

The study of membrane plasticity and the role of molecular "machines" in the control of biogenesis of the endo-cellular membranes have highlighted the crucial role of the "Rab" GTPases family as organizing centers of functional molecular platforms in membrane sub-domains. Yet, to understand the regulation and coordination of these molecular assemblies, which are responsible for cellular dynamic architectures, a more global vision, the development and the correlation of approaches at different spatial and temporal scales are needed. Focused biological models will be presented and will serve as guidelines that consider the mosaic of "Rabs domains" in particular at the plasma membrane within the context of recycling and exocytosis processes of fluorescently labeled cargos. In these In Vivo biological contexts, approaches aimed to measure and understand the multi-specific nature of these complexes have been developed. Our overall target is to model and assess the functional coordination between the different molecular machineries involved in the biogenesis of membrane sub-domains and their regulation. However, considering the "fickle" nature of such dynamic architectures, the current performance of image acquisition systems and the analytical tools at our disposal, many technological challenges must be overcome. Moreover, to extract maximum information on the same sample, the development of an adapted microscopy, correlating different modalities, is needed. Last but not least, accurate image descriptors, allowing automatic detection and classification of molecular behaviors in space and time, are indispensable.