CD-loop Extension in Zika Virus Envelope Protein Key for Stability and Pathogenesis

J Infect Dis. 2017 Dec 5;216(10):1196-1204. doi: 10.1093/infdis/jix473.


With severe disease manifestations including microcephaly, congenital malformation, and Guillain-Barré syndrome, Zika virus (ZIKV) remains a persistent global public health threat. Despite antigenic similarities with dengue viruses, structural studies have suggested the extended CD-loop and hydrogen-bonding interaction network within the ZIKV envelope protein contribute to stability differences between the viral families. This enhanced stability may lead to the augmented infection, disease manifestation, and persistence in body fluids seen following ZIKV infection. To examine the role of these motifs in infection, we generated a series of ZIKV recombinant viruses that disrupted the hydrogen-bonding network (350A, 351A, and 350A/351A) or the CD-loop extension (Δ346). Our results demonstrate a key role for the ZIKV extended CD-loop in cell-type-dependent replication, virion stability, and in vivo pathogenesis. Importantly, the Δ346 mutant maintains similar antigenicity to wild-type virus, opening the possibility for its use as a live-attenuated vaccine platform for ZIKV and other clinically relevant flaviviruses.

Keywords: Zika virus; cryo-electron microscopy; flavivirus; stability; structural virology.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Neutralizing / immunology
  • Antibodies, Viral / immunology
  • Cell Line
  • Chlorocebus aethiops
  • Disease Models, Animal
  • Epitopes / immunology
  • Female
  • Humans
  • Hydrogen Bonding
  • Male
  • Mice
  • Models, Molecular
  • Mutation
  • Protein Binding
  • Protein Conformation
  • Protein Interaction Domains and Motifs*
  • Protein Stability
  • Structure-Activity Relationship
  • Temperature
  • Vero Cells
  • Viral Envelope Proteins / chemistry*
  • Viral Envelope Proteins / genetics
  • Viral Envelope Proteins / metabolism
  • Virus Replication
  • Zika Virus / pathogenicity
  • Zika Virus / physiology*
  • Zika Virus / ultrastructure
  • Zika Virus Infection / immunology
  • Zika Virus Infection / virology*


  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Epitopes
  • Viral Envelope Proteins