Semi-isometric Registration of Line Features for Flexible Fitting of Protein Structures

• Published in: Computer graphics forum Vol. 29; no. 7; pp. 2243 - 2252
• Main Authors: Abeysinghe, S.S., Baker, M. L., Chiu, W., Ju, T.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.01.2010
• Subjects: and systems; Computer graphics; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling-Geometric algorithms; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—Geometric algorithms, languages, and systems; I.4.7 [Image Processing and Computer Vision]: Feature Measurement-Invariants; I.5.3 [Pattern Recognition]: Clustering-Similarity measures; Image coding; languages; Mapping; Optimization algorithms; Proteins; Registration; Studies
• ISSN: 0167-7055; 1467-8659; 1467-8659
• DOI: 10.1111/j.1467-8659.2010.01813.x

In this paper, we study a registration problem that is motivated by a practical biology problem – fitting protein structures to low‐re solution density maps. We consider registration between two sets of lines features (e.g., helices in the proteins) that have undergone not a single, but multiple isometric transformations (e.g., hinge‐motions). The problem is further complicated by the presence of symmetry in each set. We formulate the problem as a clique‐finding problem in a product graph, and propose a heuristic solution that includes a fast clique‐finding algorithm unique to the structure of this graph. When tested on a suite of real protein structures, the algorithm achieved high accuracy even for very large inputs containing hundreds of helices.