title: Multi-resolution anchor-point registration of biomolecular assemblies and their components.
abstract: An atomic scale interpretation facilitates the assignment of functional properties to 3D reconstructions of macromolecular assemblies in electron microscopy (EM). Such a high-resolution interpretation is typically achieved by docking the known atomic structures of components into the volumetric EM maps. Docking locations are often determined by maximizing the cross-correlation coefficient of the two objects in a slow, exhaustive search. If time is of essence, such as in related visualization and image processing fields, the matching of data is accelerated by incorporating feature points that form a compact description of 3D objects. The complexity reduction afforded by the feature point representation enables a near-instantaneous matching. We show that such reduced matching can also deliver robust and accurate results in the presence of noise or artifacts. We therefore propose a novel multi-resolution registration technique employing feature-based shape descriptions of the volumetric and structural data. The pattern-matching algorithm carries out a hierarchical alignment of the point sets generated by vector quantization. The search-space complexity is reduced by an integrated tree-pruning technique, which permits the detection of subunits in large macromolecular assemblies in real-time. The efficiency and accuracy of the novel algorithm are validated on a standard test system of homo-oligomeric assemblies.
authors.affiliation: School of Health Information Sciences, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Birmanns
authors.forename: Willy
authors.initials: W
authors.lastname: Wriggers
mesh_terms: D000465:Algorithms; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry*; D008854:Microscopy, Electron / Q000379:methods*; D008954:Models, Biological; D008958:Models, Molecular; D010363:Pattern Recognition, Automated / Q000379:methods*; D011108:Polymers / Q000737:chemistry; D025941:Protein Interaction Mapping / Q000379:methods
chemical_list: D046911:Macromolecular Substances; D011108:Polymers