Abstract

Spectral decomposition of atomic structures in heterogeneous cryo-EM

Carlos Esteve-Yague
University of Cambridge
Department of Applied Mathematics and Theoretical Physics

In this talk I will present a recent work in collaboration with Willem Diepeveen, Ozan Öktem and Carola-Bibiane Schönlieb. We consider the problem of recovering the three-dimensional atomic structure of a flexible macromolecule from a heterogeneous single-particle cryo-EM dataset. Our method combines prior biological knowledge about the macromolecule of interest with the cryo-EM images. The goal is to determine the deformation of the atomic structure in each image with respect to a specific conformation, which is assumed to be known. The prior biological knowledge is used to parametrize the space of possible atomic structures. The parameters corresponding to each conformation are then estimated as a linear combination of the leading eigenvectors of a graph Laplacian, constructed by means of the cryo-EM dataset, which approximates the spectral properties of the manifold of conformations of the underlying macromolecule.