Recent publications in The EMBO Journal (Xu et al, 2016) and in Nature Structural & Molecular Biology (Brown et al, 2016) report crystal structures of the Zika virus (ZIKV) NS1 protein. The structures reveal unique surface properties that help explain the specificity of anti‐ZIKV NS1 antibodies. Possible functions of this multifaceted pathogenicity factor are discussed here on the basis of the structures and cautious extrapolation from other flaviviruses.
See also: X Xu et al (October 2016) and
WC Brown et al (September 2016)
The contribution of X‐ray crystallography to our understanding of the re‐emerging Zika virus (ZIKV) is impressive. Nine months after the WHO declared the association of ZIKV infection with fetal microcephaly and other neurological disorders a “Public Health Emergency of International Concern”, crystal structures are available for the E protein as well as for all soluble non‐structural protein domains of the virus. Among the reasons for this swift response to the current ZIKV outbreak are methodological advances in X‐ray crystallography in the past few years and the large body of structural results available for the related dengue and West Nile viruses (DENV and WNV). As a consequence, we have more structural than functional data for most of the ZIKV non‐structural (NS) proteins at this stage. It is therefore all the more important to carefully examine the functional implications of these new structures.
One of the latest additions to the structural gallery of ZIKV is non‐structural protein 1 (NS1) (Brown et al, 2016; Xu et al, 2016). This multifunctional pathogenicity factor is the most enigmatic protein of flaviviruses. The ~50‐kD glycoprotein has beneficial effects for the flaviviruses and, paradoxically, others that are protective for the infected host. NS1 is …