New measures of anisotropy of cryo-EM maps

Jose-Luis Vilas; Hemant D Tagare

doi:10.1038/s41592-023-01874-3

New measures of anisotropy of cryo-EM maps

Nat Methods. 2023 Jul;20(7):1021-1024. doi: 10.1038/s41592-023-01874-3. Epub 2023 May 29.

Authors

Jose-Luis Vilas¹, Hemant D Tagare^{2

3}

Affiliations

¹ Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA. jlvilas@cnb.csic.es.
² Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA. hemant.tagare@yale.edu.
³ Department of Biomedical Engineering, Yale University, New Haven, CT, USA. hemant.tagare@yale.edu.

PMID: 37248387
DOI: 10.1038/s41592-023-01874-3

Abstract

We propose two new measures of resolution anisotropy for cryogenic electron microscopy maps: Fourier shell occupancy (FSO), and the Bingham test (BT). FSO varies from 1 to 0, with 1 representing perfect isotropy, and lower values indicating increasing anisotropy. The threshold FSO = 0.5 occurs at Fourier shell correlation resolution. BT is a hypothesis test that complements the FSO to ensure the existence of anisotropy. FSO and BT allow visualization of resolution anisotropy. We illustrate their use with different experimental cryogenic electron microscopy maps.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Anisotropy
Cryoelectron Microscopy*
Microscopy, Electron

Grants and funding

R01 GM125769/GM/NIGMS NIH HHS/United States