The determinant factors for map resolutions obtained using CryoEM single particle imaging method  

作　　者：Yihua Wang Daqi Yu Qi Ouyang Haiguang Liu 王义华;余大启;欧阳颀;刘海广

机构地区：[1]Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Institute of Condensed Matter Physics, School of Physics, Center for Quantitative Biology School of Physics, The Peking–Tsinghua Center for Life Sciences at School of Physics, Peking University [2]Complex Systems Division, Beijing Computational Science Research Centre

出　　处：《Chinese Physics B》2018年第12期563-571,共9页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11774011,11434001,U1530401,and U1430237)

摘　　要：The CryoEM single particle structure determination method has recently received broad attention in the field of structural biology. The structures can be resolved to near-atomic resolutions after model reconstructions from a large number of CryoEM images measuring molecules in different orientations. However, the determining factors for reconstructed map resolution need to be further explored. Here, we provide a theoretical framework in conjunction with numerical simulations to gauge the influence of several key factors to CryoEM map resolutions. If the projection image quality allows orientation assignment, then the number of measured projection images and the quality of each measurement(quantified using average signal-to-noise ratio) can be combined to a single factor, which is dominant to the resolution of reconstructed maps. Furthermore, the intrinsic thermal motion of molecules has significant effects on the resolution. These effects can be quantitatively summarized with an analytical formula that provides a theoretical guideline on structure resolutions for given experimental measurements.The CryoEM single particle structure determination method has recently received broad attention in the field of structural biology. The structures can be resolved to near-atomic resolutions after model reconstructions from a large number of CryoEM images measuring molecules in different orientations. However, the determining factors for reconstructed map resolution need to be further explored. Here, we provide a theoretical framework in conjunction with numerical simulations to gauge the influence of several key factors to CryoEM map resolutions. If the projection image quality allows orientation assignment, then the number of measured projection images and the quality of each measurement(quantified using average signal-to-noise ratio) can be combined to a single factor, which is dominant to the resolution of reconstructed maps. Furthermore, the intrinsic thermal motion of molecules has significant effects on the resolution. These effects can be quantitatively summarized with an analytical formula that provides a theoretical guideline on structure resolutions for given experimental measurements.

关 键 词：CRYO-EM RESOLUTION noise conformation heterogeneity 

分 类 号：O4[理学—物理]