Automated segmentation of molecular subunits in electron cryomicroscopy density maps

Matthew L. Baker, Zeyun Yu, Wah Chiu, Chandrajit Bajaj
2006 Journal of Structural Biology  
Electron cryomicroscopy (cryoEM) is capable of imaging large macromolecular machines composed of multiple components. However, it is currently only possible to achieve moderate resolution at which it may be possible to computationally extract the individual components in the machine. In this work, we present application details of an automated method for detecting and segmenting the components of a large machine in an experimentally determined density map. This method is applicable to object
more » ... h and without symmetry and takes advantage of global and local symmetry axes if present. We have applied this segmentation algorithm to several cryoEM data sets already deposited in EMDB with various complexities, symmetries and resolutions and validated the results using manually segmented density and available structures of the components in the PDB. As such, automated segmentation could become a useful tool for the analysis of the ever-increasing number of structures of macromolecular machines derived from cryoEM. (M.L. Baker). 1 Abbreviations used: cryoEM, electron cryomicroscopy; 3D, threedimensional; RDV, rice dwarf virus.
doi:10.1016/j.jsb.2006.05.013 pmid:16908194 fatcat:zroh7d6tlrejpenqsfk6lcygku