Chikungunya virus envelope protein E1 (E1)

The Chikungunya virus envelope protein E1 is a class II viral fusion protein essential for the entry of the Chikungunya virus (CHIKV) into host cells (UniProt Q5XXP3) [11]. It exists as a heterodimeric complex with the E2 glycoprotein on the viral surface, forming trimeric spikes that facilitate host cell recognition and attachment [5]. Upon endocytosis, the acidic environment of the endosome triggers a conformational change in E1, causing it to dissociate from E2 and form homotrimers that insert into the host endosomal membrane to mediate fusion [1, 12]. This protein is a critical determinant of viral fitness and vector specificity; for example, the A226V mutation in E1 historically enhanced CHIKV transmission by the Aedes albopictus mosquito, leading to widespread epidemics [5, 7]. E1 is a primary target for the host immune response and is a key component of vaccines, such as the live-attenuated vaccine Ixchiq (VLA1553) [5, 15]. Therapeutic research also focuses on small-molecule inhibitors and neutralizing monoclonal antibodies that target the E1 fusion loop or stabilize the E1-E2 interface to block viral entry [6, 8, 10].

Other names

CHIKV E1Spike glycoprotein E1E1 envelope glycoproteinEnvelope glycoprotein E1

Inhibition of pH-dependent membrane fusion and stabilization of the E1-E2 heterodimer to prevent viral entry and genome release.