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Cellular electron cryo tomography and in situ sub-volume averaging reveal the context of microtubule-based processes.

ABSTRACT: Electron cryo-tomography (cryoET) is currently the only technique that allows the direct observation of proteins in their native cellular environment. Sub-volume averaging of electron tomograms offers a route to increase the signal-to-noise of repetitive biological structures, such improving the information content and interpretability of tomograms. We discuss the potential for sub-volume averaging in highlighting and investigating specific processes in situ, focusing on microtubule structure and viral infection. We show that (i) in situ sub-volume averaging from single tomograms can guide and complement segmentation of biological features, (ii) the in situ determination of the structure of individual viruses is possible as they infect a cell, and (iii) novel, transient processes can be imaged with high levels of detail.

SUBMITTER: Grange M

PROVIDER: S-EPMC5287354 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Cellular electron cryo tomography and in situ sub-volume averaging reveal the context of microtubule-based processes.

Grange Michael M Vasishtan Daven D Grünewald Kay K

Journal of structural biology 20160630 2

Electron cryo-tomography (cryoET) is currently the only technique that allows the direct observation of proteins in their native cellular environment. Sub-volume averaging of electron tomograms offers a route to increase the signal-to-noise of repetitive biological structures, such improving the information content and interpretability of tomograms. We discuss the potential for sub-volume averaging in highlighting and investigating specific processes in situ, focusing on microtubule structure an ...[more]

PMID: 27374320

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