A model virus capsid assembles on and buds through a lipid bilayer membrane

Assembly and budding of a virus from a membrane microdomain. Viruses have an outer protein shell called a capsid which surrounds the viral nucleic acid. Enveloped viruses, such as HIV, have an additional layer comprising a lipid bilayer membrane which surrounds the capsid. For some enveloped viruses, the protein capsid assembles on the lipid membrane, driving deformation and eventually budding of the enveloped capsid. The video shows an animation of a computer simulation trajectory, in which a model capsid (tan) assembles within and buds through a domain (red) within a lipid bilayer membrane (blue). Such simulations enable examining how changing membrane properties affect viral budding, and may shed light on why many viruses preferentially assemble from membrane microdomains such as lipid rafts.