Label-free assembly of RNA-containing viruses, one particle at a time

forthcoming

Self-assembly of individual proteins into a virus is fascinatingly efficient. It is fast and highly accurate, and occurs without an external energy source. While the pre- and post-assembly states are well characterised, the study of assembly itself is notoriously difficult, due to the small (nanometre) size of viral shells and the transient nature of the assembly intermediates. The actual process of virus assembly remains in fact poorly understood. In this project, I focus on the pathogens responsible for the diseases AIDS and COVID-19, the two major pandemics of the last 50 years. The causative agents of these pandemics are the RNA-containing viruses HIV and SARS-CoV-2, respectively. Using high-speed atomic force microscopy, I will capture individual intermediate states in the course of viral assembly. This cutting-edge technique will be complemented by optical tweezers studies. These orthogonal, label-free single-particle approaches will allow me to visualize assembly in near-to-native environments to elucidate the dynamics of this process. Furthermore, I will study assembly around the native RNA genome of these viruses. Finally, the modes of action of antiviral drugs that target assembly will be identified. The generated new insights into assembly are essential for understanding, using and combatting viral particles better. Recent developments in single-particle techniques allow to achieve ground-breaking advances in our comprehension of viral assembly. My long-standing experience in viral studies, atomic force microscopy and optical tweezers will be expanded with 3D high-speed imaging and probing of RNA-based viral dynamic processes. The expected results will greatly enhance our knowledge of the fundamental physics and biology of how protein complexes (dis)assemble, which is crucial for our understanding of viral life cycles and disease, for nanotechnological approaches using self-assembling nanoparticles, and for the rational design of new antiviral drugs.