Host Cell-Zika Virus Interaction Determined by Envelope Protein Structure

Zika is a flavivirus similar to dengue and West Nile viruses. The Zika virus was first isolated in the Zika forest in Uganda in 1947. Rapid proliferation of Zika can be attributed to a lack of immunity and its unique protein structure. Once the virus enters the host cell, a change in pH causes a conformational change of the envelope (E) protein which releases the viral RNA into the cell. The E protein is a dimer in which each monomer is composed of three domains. Domain I contains a potential glycosylation site, an asparagine amino acid, at position 154. The sugar at this site may serve to bind the virus to host cells. In addition, glycosylation at this site may control the amount of solvent able to access the fusion loop in Domain II, affecting the wide array of cells the virus can infect. The five amino acids around the glycosylation site unique to Zika may also affect the virus’s sensitivity to antibodies that bind the fusion loop. Because of Zika’s mass proliferation and potential to cause birth defec...