Theoretical modelling of the assembly of small Icosahedral viruses

Abstract

One of the key steps in the replication of a virus is the self-assembly of the capsid, which is a protein shell protecting the genetic material inside. The capsid plays an important role in the virus, and understanding its formation process would open the door to the development of new antiviral therapies. The aim of this work is to study theoretically the self-assembly of the smallest empty capsids, ignoring the presence of the genetic material. We formulate and compare a discrete description of viral assembly with a continuous approximation based on Classical Nucleation Theory. We have estimated the line tension involved in the formation of a partial icosahedral shell. Besides, we have solved numerically the Master equation using the estimated line tension in order to predict the nucleation rate for different concentrations. The results of our study show that Classical Nucleation Theory is valid even for very small viruses and can be a very powerful framework to analyze in vitro viral assembly experiments.