Hyatt James G, Prévost Sylvain, Devos Juliette M, Mycroft-West Courtney J, Skidmore Mark A, Winter Anja
School of Life Sciences, Keele University, Huxley Building, Keele, Staffordshire ST5 5BG, UK.
Large Scale Structures Group, Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, 38042 Grenoble CEDEX 9, France.
Pathogens. 2020 Nov 11;9(11):935. doi: 10.3390/pathogens9110935.
Dengue fever is a rapidly emerging vector-borne viral disease with a growing global burden of approximately 390 million new infections per annum. The Dengue virus (DENV) is a flavivirus spread by female mosquitos of the genus, but the mechanism of viral endocytosis is poorly understood at a molecular level, preventing the development of effective transmission blocking vaccines (TBVs). Recently, glycosaminoglycans (GAGs) have been identified as playing a role during initial viral attachment through interaction with the third domain of the viral envelope protein (EDIII). Here, we report a systematic study investigating the effect of a range of biologically relevant GAGs on the structure and oligomeric state of recombinantly generated EDIII. We provide novel in situ biophysical evidence that heparin and chondroitin sulphate C induce conformational changes in EDIII at the secondary structure level. Furthermore, we report the ability of chondroitin sulphate C to bind EDIII and induce higher-order dynamic molecular changes at the tertiary and quaternary structure levels which are dependent on pH, GAG species, and the GAG sulphation state. Lastly, we conducted ab initio modelling of Small Angle Neutron Scattering (SANS) data to visualise the induced oligomeric state of EDIII caused by interaction with chondroitin sulphate C, which may aid in TBV development.
登革热是一种迅速出现的媒介传播病毒性疾病，全球负担日益加重，每年约有3.9亿新感染病例。登革病毒（DENV）是一种黄病毒，由该属的雌性蚊子传播，但在分子水平上对病毒内吞作用机制了解甚少，这阻碍了有效的传播阻断疫苗（TBV）的研发。最近，已确定糖胺聚糖（GAGs）在病毒最初附着过程中通过与病毒包膜蛋白的第三结构域（EDIII）相互作用发挥作用。在此，我们报告了一项系统研究，调查一系列具有生物学相关性的GAGs对重组生成的EDIII的结构和寡聚状态的影响。我们提供了新的原位生物物理证据，表明肝素和硫酸软骨素C在二级结构水平上诱导EDIII发生构象变化。此外，我们报告了硫酸软骨素C结合EDIII并在三级和四级结构水平上诱导高阶动态分子变化的能力，这些变化取决于pH值、GAG种类和GAG硫酸化状态。最后，我们对小角中子散射（SANS）数据进行了从头建模，以可视化与硫酸软骨素C相互作用引起的EDIII诱导寡聚状态，这可能有助于TBV的研发。
