National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
U24GM139166
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
U24GM129541
米国
引用
ジャーナル: Structure / 年: 2025 タイトル: Cost-benefit analysis of cryogenic electron tomography subtomogram averaging of chaperonin MmCpn at near atomic resolution. 著者: Yanyan Zhao / Michael F Schmid / Wah Chiu / 要旨: Cryogenic electron microscopy single particle analysis (cryoEM-SPA) has evolved into a routine approach for determining macromolecule structures to near-atomic resolution. Cryogenic electron ...Cryogenic electron microscopy single particle analysis (cryoEM-SPA) has evolved into a routine approach for determining macromolecule structures to near-atomic resolution. Cryogenic electron tomography subtomogram averaging (cryoET-STA) toward a similar resolution, in contrast, is still under active development. Here, we use the archeal chaperonin MmCpn as a model macromolecule to quantitatively investigate the resolution limiting factors of cryoET-STA in terms of cumulative electron dose, ice thickness, subtomogram numbers, and tilt angle ranges. By delineating the feasibility and experimental factors of attaining near atomic resolution structure with cryoET-STA, especially the effect of electron damage through the tilt series and inelastic scattering at various ice thickness, we encourage a customized tilt series collection strategy for efficient throughput. This study provides a biophysical basis for the application of cryoET-STA (for highly symmetric molecules like MmCpn) toward high resolution and the rationales in using cryoET-STA to achieve an efficient outcome at the desired resolution.