Mechanisms of budding of virus particles through a spherical vesicle*

We investigate the process of nucleocapsid core budding through the cell membrane, forming the outer lipid membrane of envelop viruses. Our study combines analytical and numerical methods, along with a coarse-grained model and molecular dynamics simulations, to examine budding dynamics in relation to membrane curvature. There is a competition between bending energy of the membrane and the attractive interaction between the membrane and nucleocapsid. We identify the key variables such as surface tension, protein radius and spontaneous curvature, which changes energy barrier for budding. Our study shows that budding through spherical vesicles has a lower energy barrier compared to budding through flat membranes. Understanding the factors influencing virus budding provides valuable knowledge to design interventions that prevent virus assembly.