傅里叶壳相关排序检验法在冷冻电镜映射分辨率估计中的应用。

Permutation testing of Fourier shell correlation for resolution estimation of cryo-EM maps.

机构信息

European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany; Candidate for Joint PhD degree from EMBL and Heidelberg University, Faculty of Biosciences, Germany; Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons (ER-C-3/Structural Biology), Forschungszentrum Jülich, 52425 Jülich, Germany; JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany.

European Molecular Biology Laboratory (EMBL), Structural and Computational Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany; Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons (ER-C-3/Structural Biology), Forschungszentrum Jülich, 52425 Jülich, Germany; JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, 52425 Jülich, Germany; Department of Chemistry, Heinrich Heine University, Universitätsstraße 1, 40225 Düsseldorf, Germany.

出版信息

J Struct Biol. 2020 Oct 1;212(1):107579. doi: 10.1016/j.jsb.2020.107579. Epub 2020 Jul 18.

DOI:10.1016/j.jsb.2020.107579

PMID:32693019

Abstract

Fourier shell correlation (FSC) has become a standard quantity for resolution estimation in electron cryo-microscopy. However, the resolution determination step is still subjective and not fully automated as it involves a series of map interventions before FSC computation and includes the selection of a common threshold. Here, we apply the statistical methods of permutation testing and false discovery rate (FDR) control to the resolution-dependent correlation measure. The approach allows fully automated and mask-free resolution determination based on statistical thresholding of FSC curves. We demonstrate the applicability for global, local and directional resolution estimation and show that the developed criterion termed FDR-FSC gives realistic resolution estimates based on statistical significance while eliminating the need of any map manipulations. The algorithms are implemented in a user-friendly GUI based software tool termed SPoC (https://github.com/MaximilianBeckers/SPOC).

摘要

傅里叶壳相关（Fourier shell correlation，FSC）已成为电子晶体学中分辨率估计的标准量。然而，分辨率确定步骤仍然是主观的，并且没有完全自动化，因为它在 FSC 计算之前涉及一系列映射干预，并且包括选择共同的阈值。在这里，我们将置换检验和错误发现率（false discovery rate，FDR）控制的统计方法应用于分辨率相关的相关度量。该方法允许基于 FSC 曲线的统计阈值进行全自动和无掩模分辨率确定。我们展示了全局、局部和方向分辨率估计的适用性，并表明开发的基于 FDR 的 FSC 标准在消除任何映射操作的同时，基于统计显著性给出了现实的分辨率估计。该算法已在一个名为 SPoC（https://github.com/MaximilianBeckers/SPOC）的基于用户友好的图形用户界面（graphical user interface，GUI）的软件工具中实现。