| Autor: |
Crampon, E., Covernton, E., Vaney, M.C., Dellarole, M., Sharma, A., Haouz, A., England, P., Lepault, J., Duquerroy, S., Rey, F.A., Barba-Spaeth, Giovanna |
| Přispěvatelé: |
Virologie Structurale - Structural Virology, Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Cristallographie (Plateforme) - Crystallography (Platform), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Biophysique Moléculaire (plateforme) - Molecular Biophysics (platform), Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris] (IP), This work was supported by the French ANR (Agence Nationale de la Recherche), grants ANR-17-CE15-0031-01 FLAVIMMUNITY to GBS., We thank the staff at beamlines PX1 and PX2 at Soleil synchrotron (St. Aubin, France) and at PX beamlines at the ESRF (Grenoble, France), Franz X. Heinz and Karin Stiasny from Center for Virology, Medical University of Vienna, Austria for the gift of DENV pr protein and the plasmid for the production of ZIKV PF13 sE protein, Pablo Guardado-Calvo and Ignacio Fernandez from the Rey lab for helping with the MALS experiments and Alexander Rouvinski for help with the setting of the fusion experiments., ANR-17-CE15-0031,FLAVIMMUNITY,Comprendre les mécanismes de l'efficacité du vaccin de la fièvre jaune 17D: Une approche immuno-structurelle vers la conception d'un vaccin Pan-flavivirus(2017) |
| Rok vydání: |
2022 |
| Předmět: |
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| Popis: |
Flavivirus particles bud in the ER of infected cells as immature virions composed of 180 heterodimers of glycoproteins prM and E, associated as 60 (prM/E)3trimeric spikes. Exposure to the mildly acidic pH of the TGN results in dissociation of the trimeric spikes followed by reassociation of the prM/E protomers into 90 dimers organized in a characteristic herringbone pattern. The furin site in prM is exposed in the dimers for maturation of prM into M and pr. For flaviviruses such as the tick-borne encephalitis virus (TBEV) as well as for dengue virus, it was shown that at neutral pH pr loses affinity for E, such that it dissociates from the mature particle as soon as it reaches the external milieu, which is at neutral pH. Using a soluble recombinant form of E (sE) and pr from yellow fever virus (YFV), we show here that the affinity of pr for recombinant E protein remains high even at neutral pH. The X-ray structure of YFV pr/sE shows more extensive inter-chain hydrogen bonding than does the dengue or TBEV, and also that it retains the charge complementarity between the interacting surfaces of the two proteins even at neutral pH. We further show that pr blocks sE flotation with liposomes when exposed at low pH at a 1:1 stoichiometry, yet in the context of the virus particle, an excess of 10:1 pr:E ratio is required to block virus/liposome fusion. In aggregate, our results show that the paradigm obtained from earlier studies of other flaviviruses does not apply to yellow fever virus, the flavivirus type species. A mechanism that does not rely solely in a change in the environmental pH is thus required for the release of pr from the mature particles upon release from infected cells. These results open up new avenues to understand the activation mechanism that yields mature, infectious YFV particles. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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