Flavivirus membrane fusion

Institute of Virology, Medical University of Vienna, Kinderspitalgasse 15, A1095 Vienna, Austria.
Journal of General Virology (Impact Factor: 3.18). 11/2006; 87(Pt 10):2755-66. DOI: 10.1099/vir.0.82210-0
Source: PubMed


Flavivirus membrane fusion is mediated by a class II viral fusion protein, the major envelope protein E, and the fusion process is extremely fast and efficient. Understanding of the underlying mechanisms has been advanced significantly by the determination of E protein structures in their pre- and post-fusion conformations and by the elucidation of the quarternary organization of E proteins in the viral envelope. In this review, these structural data are discussed in the context of functional and biochemical analyses of the flavivirus fusion mechanism and its characteristics are compared with those of other class II- and class I-driven fusion processes.

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    • "Yellow fever virus is a Category C pathogen. The E protein of yellow fever virus (YFE) plays multiple roles during cell infection (Kaufmann and Rossmann, 2011;Smit et al., 2011;Stiasny and Heinz, 2006) and induces virus-neutralizing antibodies and protective immunity (), which makes it a key target in the development of a subunit vaccine against yellow fever (Despr es et al., 1988Despr es et al., , 1991). Recently, the Fraunhofer USA Center for Molecular Biotechnology has engineered and expressed YFE in N. benthamiana (Tottey, S., Shoji, Y., Jones, R.M., Chichester, J.A., Green, B.J., Musiychuk, K., Shamloul, M., Norikane, J., da Silva Friere, M., Caride, E.C., Homma, A., Cuber Guimarã es, R., Streatfield, S.J., Yusibov, V., in preparation.). "
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    ABSTRACT: Despite progress in the prevention and treatment of infectious diseases, they continue to present a major threat to public health. The frequency of emerging and reemerging infections and the risk of bioterrorism warrant significant efforts towards the development of prophylactic and therapeutic countermeasures. Vaccines are the mainstay of infectious disease prophylaxis. Traditional vaccines, however, are failing to satisfy the global demand because of limited scalability of production systems, long production timelines and product safety concerns. Subunit vaccines are a highly promising alternative to traditional vaccines. Subunit vaccines, as well as monoclonal antibodies and other therapeutic proteins, can be produced in heterologous expression systems based on bacteria, yeast, insect cells or mammalian cells, in shorter times and at higher quantities, and are efficacious and safe. However, current recombinant systems have certain limitations associated with production capacity and cost. Plants are emerging as a promising platform for recombinant protein production due to time and cost efficiency, scalability, lack of harboured mammalian pathogens and possession of the machinery for eukaryotic post-translational protein modification. So far, a variety of subunit vaccines, monoclonal antibodies and therapeutic proteins (antivirals) have been produced in plants as candidate countermeasures against emerging, reemerging and bioterrorism-related infections. Many of these have been extensively evaluated in animal models and some have shown safety and immunogenicity in clinical trials. Here, we overview ongoing efforts to producing such plant-based countermeasures.
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    • "Infected by Japanese encephalitis virus is initiated by fusion between the viral membrane and the host membrane. The fusion process is mediated by the Japanese encephalitis virus Envelope protein in a pH-dependent manner (Stiasny and Heinz 2006). "
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    Full-text · Article · Mar 2015 · International Journal of Applied Biology and Pharmaceutical Technology
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    • "Domain III, at E's C-terminus, helps the virus target cell receptors, leading to endocytosis [7] [8] [9] [10] [11] [12] [13] [14]. Once inside the endosome, a low pH-driven conformational change of E results in exposure of hydrophobic residues at the tip of the beta-structured Domain II that attach E to the host endosomal membrane and promote virus–membrane fusion (Fig. 1) [15] [16]. "
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