EDUCATIONAL ARTICLE: Structural analysis of viral factories: From conventional microscopy to electron tomography
Abstract
Viral factories are large structures built by cellular and viral components where viruses insert the Macromolecular complexes needed for genome replication and morphogenesis of new viral particles. We are studying how factories are built and work with the assistance of a variety of electron microscopy (EM) methods. Our goal is to obtain three-dimensional (3D) maps of these very complex structures to study how replication complexes are formed, how replicated genomes are transferred to assembly sites and how new, infectious viral particles assemble and mature inside the factories. In the present work we revise EM techniques that provide 3D information of cells to describe how we can apply them to characterize the complex organization of virus factories. Reconstructions from serial sections and metal replicas after freeze-fracture provide 3D maps of medium resolution that we plan to use as complementary tools to assist in the interpretation of the very complex maps of cells to be obtained by electron tomography (ET). Within this context viruses are providing us with models to understand cellular trafficking pathways and cell architecture.