Membrane Fusion

Entry of enveloped viruses is mediated by viral glycoproteins that catalyze fusion of viral and cellular membranes. These viral glycoproteins need to be activated which leads to extensive conformational changes that trigger the insertion or attachment of a fusion peptide in or to cellular target membranes thus bridging two bilayers. Further refolding into a hairpin-like structure pulls viral and cellular membranes into close apposition, a process that leads to lipid bilayer fusion. Although viral fusion proteins belong to three different classes based on their structural organization, they follow similar structural principles to achieve fusion.