Electron tomography (ET) is a method for obtaining 3D-structural information using TEM. The images of a tilt series are acquired over a wide range of viewing angles, and then these 2D-projection images are aligned and back-projected to generate a 3D-reconstruction. In biological research, ET can be applied to study unique structures, which are in the context of a cell. ET is ideally suited to reveal cell organelles ultra structure in the 5-20 nm resolution range.
The first movie (on the left) shows serial tilted views of the 120 nm thick section from a cell of Trypanosoma brucei . Images were collected (TEM Tecnai F20) at one degree intervals over a range from -62° to +62° at magnification of 11500x. Gold particles (10 nm) were used as fiducial markers to align the images of the raw dataset (H. Vihinen).
The second movie (on the left) shows a serial section reconstruction of a fragment of a cell of Trypanosoma brucei (H. Vihinen).
The third movie (on the left) shows the modeled Golgi complex and ER of a cell of Trypanosoma brucei. The membranes of rough endoplasmic reticulum are coloured as yellow and Golgi in shapes of blue (Eija Jokitalo and Ilya Belevich).
Image alignment and reconstruction are done utilizing IMOD software package (The Boulder Laboratory for 3-Dimensional Electron Microscopy of Cells, University of Colorado). The segmentation was done in Microscopy Image Browser, the final model visualized with Amira (ThermoFisher Scientific).