Cryo-electron Tomography (cryo-ET)

Introduction to Cryo-electron Tomography

Cryo-ET (also known as electron cryotomography) is a technique for analyzing protein-protein interactions in their native and functional state in three-dimensional molecular resolution. The sample is imaged in a series of two-dimensional images as it is tilted in a controlled series of positions. The resulting image “slices” can then be combined to produce a 3D reconstruction of the sample. MaTestLab is one of the leading testing service providers in the USA and Canada. We have a large network of testing laboratories in the USA.

Principle and Methodology of Cryo-electron Tomography

In a cryo-ET investigation, a biological sample—a cell, tissue, or organism—is flash frozen, thinned to a suitable thickness, then examined using an electron microscope. The freezing technique keeps the sample hydrated and close to its native state. The sample is tilted along an axis, resulting in several pictures. The photos are then aligned and combined with computer techniques to create a three-dimensional image, or tomogram.

Instrumentation

Cryo-ET uses sophisticated instrumentation for high-resolution imaging, from a cryo-electric microscope, direct electron detectors, tilt stage, to image processing software. A cryo-electric microscope keeps the samples at a very low temperature. The detector captures low-noise images, whereas the tilt stage enables the capture of 2D projection images. In turn, image-processing software aligns and reconstructs a 3D tomogram from the obtained 2D images using computational tools.

Applications of Cryo-electron Tomography

Cryo-electron tomography (CryoET) is utilized to resolve biomolecules within their biological environment at extraordinary subnanometer precision, providing a window into molecular sociology. It is a scale in which individual proteins may be identified solely by their form, with no tagging.

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