Metal-replica EM in the 21st century
14 juin 2018 à 11:30 (Amphi Broca Nouvelle Aquitaine / Campus Carreire)
Myologie Centre de Recherche/Paris
Institut de Myologie UMRS 974 UPMC-Inserm, FRE 3617 CNRS
Invitant : David Perrais
PhD, IINS , team: Nano-scale organization, dynamics of synaptic proteins and membrane trafficking.
In cell biology, particular importance is given to developing new methods of sample preparation that will achieve a more natural appearance of samples in the microscope. To accomplish this, scientists have developed the metal-replica electron microscopy (EM) technique directly on unroofed cultured cells. This particular EM technique permits visualization of the inner side of cell membranes and their components. Metal-replicas have profoundly shaped our understanding of the functional morphology of the cell and used to capture several different cellular processes including remodeling of cytoskeletons, membrane trafficking, cell-to-cell contacts and formation of extracellular matrices. Combined to transmission electron microscopy (TEM), it is an invaluable method to reveal the composition of the PM and to directly observe macromolecular complexes including the cytoskeleton and endocytic membrane invaginations at high resolution. Here, I will outline the history of this particular EM technique and describe different methodologies and some key applications in cell biology including visualization of the cytoskeleton and different endocytic structures such as clathrin coated pits and caveolae.
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