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bioRxiv · 10.1101/363317

Structure of the ciliary axoneme at nanometer resolution reconstructed by TYGRESS

Song, K.·Shang, Z.·Fu, X.·Lou, X.·Grigorieff, N.·Nicastro, D.
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Abstract

The resolution of subtomogram averages calculated from cryo-electron tomograms (cryo-ET) of crowded cellular environments is often limited due to signal loss in, and misalignment of the subtomograms. In contrast, single-particle cryo-electron microcopy (SP-cryo-EM) routinely reaches near-atomic resolution of isolated complexes. We developed a novel hybrid-method called \"TomographY-Guided 3D REconstruction of Subcellular Structures\" (TYGRESS) that combines cryo-ET with SP-cryo-EM to achieve close-to-nanometer resolution of complexes inside crowded environments. Using TYGRESS, we determined the native 3D structures of the intact ciliary axoneme with up to 12 [A] resolution. These results reveal many structures and details that were not visible by cryo-ET. TYGRESS is generally applicable to cellular complexes that are amenable to subtomogram averaging, bringing us a step closer to (pseudo-)atomic models of cells.\n\nOne Sentence SummaryA hybrid cryo-electron microscopy method reveals subcellular structures at unprecedented resolution.

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Song, K., Shang, Z., Fu, X., Lou, X., Grigorieff, N., Nicastro, D.. 2018-07-06. Structure of the ciliary axoneme at nanometer resolution reconstructed by TYGRESS. https://doi.org/10.1101/363317

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