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bioRxiv · 10.64898/2026.02.03.703505

Robust quality assessment of cryo-EM maps, tomograms and micrographs by statistics-based local resolution estimation

Kartte, D.·Sachse, C.
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Abstract

Resolution estimation by Fourier shell correlation (FSC) using half data sets is the standard method for map quality assessment in cryo-EM. Currently, the FSC method is largely used for refined cryo-EM maps in the context of single particle cryo-EM or subtomogram averaging. Here, we extended resolution estimation to assess the quality of electron micrographs, tilt-series and tomograms. We developed a robust statistics-based framework, capable of determining local quality estimates in the above cryo-EM data types. We show that the determined quality values on a micrograph and tomogram level can be used as a particle quality criterion to improve averaged 3D reconstructions. Using local quality assessments of tomograms, we were able to characterize tomogram quality dependence on distance inferred by radiation damage of FIB-milled lamella. This robust resolution-based quality assessment approach suitable for multiple cryo-EM data types opens new possibilities for automated quality control and method development in cryo-EM maps as well as tomograms and micrographs.

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Kartte, D., Sachse, C.. 2026-02-05. Robust quality assessment of cryo-EM maps, tomograms and micrographs by statistics-based local resolution estimation. https://doi.org/10.64898/2026.02.03.703505

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