The molecular structure of nonstructural protein 1 (NS1) from Zika virus (ZIKV) is reported in a paper published online this week in Nature Structural & Molecular Biology. The work provides an atomic view of a protein that is involved in viral pathogenesis in related viruses such as dengue and West Nile viruses.
Mosquito-borne ZIKV is currently causing an epidemic in the Americas. Although infection with ZIKV usually causes mild symptoms, the virus has been linked to microcephaly - in which children are born with abnormally small heads - and a rare autoimmune disease called Guillain-Barre syndrome, thus leading the World Health Organization to declare it a public health emergency. ZIKV is a flavivirus related to dengue and West Nile viruses. Dengue NS1 is important for viral pathogenesis; it is also used to diagnose infection and is a proposed target for antiviral drug development.
George Gao, Yi Shi and colleagues used X-ray crystallography to obtain the structure of an NS1 fragment based on the sequence of a ZIKV strain isolated in Brazil in 2015. They found that ZIKV NS1 is largely similar to dengue and West Nile NS1, but that ZIKV NS1 is substantially different in the distribution of electrical charges (positive or negative) on its surface, characteristics that may be related to different interactions with host factors. The authors conclude that the unique surface electrostatic characteristics of ZIKV NS1 may be useful in the development of new diagnostic tools for ZIKV infection.
The paper will be free to access until further notice, per an agreement among publishers and research funders to ensure that the global response to public health emergencies is informed by the best available research evidence and data.