2024Zhu SIRM
Citation
Zhu, Dongjie / Cao, Weili / Li, Junxi / Wu, Chunling / Cao, Duanfang / Zhang, Xinzheng. Correction of preferred orientation--induced distortion in cryo-electron microscopy maps. 2024. Science Advances, Vol. 10, No. 30, p. eadn0092
Abstract
Reconstruction maps of cryo–electron microscopy (cryo-EM) exhibit distortion when the cryo-EM dataset is incomplete, usually caused by unevenly distributed orientations. Prior efforts had been attempted to address this preferred orientation problem using tilt-collection strategy and modifications to grids or to air-water interfaces. However, these approaches often require time-consuming experiments, and the effect was always protein dependent. Here, we developed a procedure containing removing misaligned particles and an iterative reconstruction method based on signal-to- noise ratio of Fourier component to correct this distortion by recovering missing data using a purely computational algorithm. This procedure called signal-to- noise ratio iterative reconstruction method (SIRM) was applied on incomplete datasets of various proteins to fix distortion in cryo-EM maps and to a more isotropic resolution. In addition, SIRM provides a better reference map for further reconstruction refinements, resulting in an improved alignment, which ultimately improves map quality and benefits model building.
Keywords
Links
https://www.science.org/doi/full/10.1126/sciadv.adn0092