Chikungunya virus envelope glycoprotein E1 (E1)

The Chikungunya virus envelope glycoprotein E1 is a class II fusion protein embedded in the virion lipid bilayer, forming heterodimers with E2 (derived from p62 precursor after furin cleavage) that trimerize into 80 icosahedral spikes (T=4 symmetry). It drives low pH-dependent membrane fusion during endosomal entry by exposing its fusion loop (residues 83-100 in domain II), inserting into the host membrane, and trimerizing. E1 also contributes to virus attachment by modulating E1-E2 interactions and binding to glycosaminoglycans like heparin/heparan sulfate, influences receptor interactions (e.g., Mxra8 via E2 changes), stabilizes the glycoprotein lattice through E1-E1 interspike contacts, and supports particle assembly, egress, and immunogenicity. Mutations (e.g., V156A, K211T, M88L, N20Y) alter E2 conformation, cell-type-specific infectivity, GAG binding, antibody neutralization, and pathogenesis in mice and insects.

Other names

Chikungunya virus E1 glycoproteinCHIKV E1p62-E1 heterodimer precursor component (mature form after furin cleavage)