title: A fast cross-validation method for alignment of electron tomography images based on Beer-Lambert law.
abstract: In electron tomography, accurate alignment of tilt series is an essential step in attaining high-resolution 3D reconstructions. Nevertheless, quantitative assessment of alignment quality has remained a challenging issue, even though many alignment methods have been reported. Here, we report a fast and accurate method, tomoAlignEval, based on the Beer-Lambert law, for the evaluation of alignment quality. Our method is able to globally estimate the alignment accuracy by measuring the goodness of log-linear relationship of the beam intensity attenuations at different tilt angles. Extensive tests with experimental data demonstrated its robust performance with stained and cryo samples. Our method is not only significantly faster but also more sensitive than measurements of tomogram resolution using Fourier shell correlation method (FSCe/o). From these tests, we also conclude that while current alignment methods are sufficiently accurate for stained samples, inaccurate alignments remain a major limitation for high resolution cryo-electron tomography.
authors.affiliation: Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Yan
authors.affiliation: Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Edwards
authors.affiliation: Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Logan M
authors.initials: LM
authors.lastname: Pankratz
authors.affiliation: Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Kuhn
authors.affiliation: Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Jason K
authors.initials: JK
authors.lastname: Lanman
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Markey Center for Structural Biology, Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA. Electronic address: jiang12@purdue.edu.
authors.forename: Wen
authors.initials: W
authors.lastname: Jiang
mesh_terms: D000465:Algorithms; D020285:Cryoelectron Microscopy / Q000379:methods*; D055032:Electron Microscope Tomography / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D016018:Least-Squares Analysis
keywords: Alignment accuracy; Beer–Lambert law; Cross validation; Electron tomography; Inelastic scattering; Least square fitting