(Cryo) Electron tomography

Structural analysis from molecular to a cellular level

Electron tomography is a non-invasive, high resolution imaging technique that allows the visualisation of 3D organization of eukaryotic cells, with their dynamic organelles, cytoskeletal structures and molecular machines when combined with a method of arresting cells in their momentary state of function. Cellular structural biology is now becoming accessible by combining together different structural techniques. In this context, one of our goals is to investigate structure, dynamics, transmission and selectivity of viral complexes from molecular to cellular levels.

A and B : micrographs of frozen jurkat cells, where you can see the membrane, vesicles and the actin filaments. C : CryoEM-tomogram section of HeLa cells.

Cryo Electron Microscope

Vitrobot (ThermoFischer)

Pumping Station (Gatan) for cryo holders

Analysis or screening of negative stained sample

Routine check of your samples

After purification of the protein complexe of interest, a negative stained grid of the sample is done. You can use this microscope to check your sample quality. It is a very easy and fast way to tell if the protein solution is homogenous, stable and a suitable candidate for high resolution structure analysis in cryo. You can also use this microscope to do room temperature tomography analysis.

Micrograph of V2 protein complexes and 2D classes, DNA origami structures and 2D classes and cells section.

JEOL 1400 Flash Microscope

Structural analysis of frozen hydrated single particles

Structure of protein complexes at high resolution

After purification of the protein complexe of interest, a negative stained grid of the sample is done. It is a very easy and fast way to tell if the protein solution is homogenous, stable and a suitable candidate for high resolution structure analysis. Then, the best protocol is used to prepare the frozen hydrated samples (good spreading of the protein complexe on the cryo grids). Images are then acquired (more than thousands images). A selection of the best images is done and 2D and 3D analysis are performed on each protein complexe particles (usually close to millions of particles).

Micrograph of ribosomes particles and the corresponding 3D structure

Cryo Electron Microscope

Vitrobot (ThermoFischer)

Pumping Station (Gatan) for cryo holders