Geometric shape matching for recovering protein conformations from single-particle Cryo-EM data
This work aims to improve the accuracy of 3D protein structure determination for biologists and biochemists, which is an incremental improvement in a well-established field.
This paper addresses the recovery of 3D protein backbone structures from noisy 2D tomographic projections obtained via single-particle cryo-electron microscopy (Cryo-SPA). The authors propose a method that deforms a point cloud representation of the protein backbone to match the 2D tomography data, achieving successful 3D structure recovery on synthetic data.
We address recovery of the three-dimensional backbone structure of single polypeptide proteins from single-particle cryo-electron microscopy (Cryo-SPA) data. Cryo-SPA produces noisy tomographic projections of electrostatic potentials of macromolecules. From these projections, we use methods from shape analysis to recover the three-dimensional backbone structure. Thus, we view the reconstruction problem as an indirect matching problem, where a point cloud representation of the protein backbone is deformed to match 2D tomography data. The deformations are obtained via the action of a matrix Lie group. By selecting a deformation energy, the optimality conditions are obtained, which lead to computational algorithms for optimal deformations. We showcase our approach on synthetic data, for which we recover the three-dimensional structure of the backbone.