Toward Unbiased 3D Reconstruction of Flexible Single-Particle

Program Description

Cryo-electron microscopy and single-particle 3D reconstruction plays a pivotal role in the difficult and pressing challenge of determining the structures of large macromolecular complexes, such as ribosomes and general transcription factors. Molecular volumes are generated by aligning large sets of very noisy 2D projection images with unknown and random orientations in 3D before volume interpolation. The increasing popularity of single-particle methods in structural biology is highly correlated with technical advances in instrumentation and computation. In this talk, Stanford Postdoc Hans Olof Elmlund will present new computational tools for ab initio 3D reconstruction from challenging single-particle populations (low-contrast, no symmetry, significant degree of structural heterogeneity, etc). The methods do not rely on a priori information about the structure or the sample heterogeneity, making them applicable to a wide range of single-particles. I will introduce the core algorithms of SIMPLE (Single-particle IMage Processing Linux Engine) and give examples of reconstructions that have given insights into the fundamental biological processes of transcription and translation.