Chikungunya Virus Structural Proteins (CHIKV Structural Proteins)

Chikungunya virus (CHIKV) structural proteins are essential for viral assembly, maturation, and infectivity. These proteins include the capsid protein (C), envelope glycoproteins E1, E2, and E3, and the 6K protein. They are produced from a single open reading frame and processed through proteolytic cleavage. Mature virions display trimeric spikes composed of E1-E2 heterodimers, which mediate host cell attachment and membrane fusion. E3 regulates spike precursor folding but is released during maturation. 6K assists in translocation and processing of the structural polyprotein. The structure has been resolved using cryo-electron microscopy. The main proteins are C, E1, E2, E3, and 6K. C forms the core/nucleocapsid around genomic RNA. Surface spikes consist mainly of heterodimers/trimeric complexes involving glycosylated envelope proteins and are primarily responsible for cell attachment/fusion. Proper maturation requires post-translational cleavage events that release or rearrange these components to yield infectious particles.