Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rift Valley fever virus: An infection mechanism identified

13.11.2017

Rift Valley fever virus, transmitted by mosquitoes, is responsible for outbreaks in livestock in Africa and can also be fatal in humans. Scientists from the Institut Pasteur and the CNRS, working with the University of Göttingen, have characterized the mechanism used by the virus to insert one of its envelope proteins into the host cell membrane, thereby enabling it to infect the cell.

They have demonstrated that the viral envelope protein has a "pocket" that specifically recognizes a category of lipids in the cell membrane. This pocket is also found in other human pathogenic viruses transmitted by different mosquitoes, such as the Zika and chikungunya viruses.


Model of the Rift Valley virus fusion protein interacting with a cell membrane (in white and green), obtained using molecular dynamics. The enlargement shows the lipid head 'recognition pocket', with the protein represented at the surface.

Credit: © Pablo Guardado-Calvo, Institut Pasteur

Understanding these interactions should pave the way for the identification of new therapeutic strategies that target viruses transmitted by these mosquitoes. The findings were published in the journal Science on November 3, 2017.

Rift Valley fever (RVF) virus is a bunyavirus that was first isolated from sheep in Kenya in 1930. The spread of RVF has serious economic consequences in Africa. The virus also causes severe disease in humans who come into contact with contaminated animals or who are bitten by infected mosquitoes, resulting in severe encephalitis and hemorrhagic fever that can prove fatal.

RVF therefore also represents a significant public health threat. In 2000, the virus spread outside the African continent to Saudi Arabia and Yemen. There are concerns that it may also extend to Asia and Europe.

RVF virus spreads in its host by fusing with cell membranes so that it can proliferate and infect other cells. Scientists in the Structural Virology Unit (Institut Pasteur/CNRS) directed by Félix Rey, in collaboration with the University of Göttingen, characterized the mechanism used by the virus to insert one of its surface proteins into the host cell membrane and drive fusion.

They also determined the atomic structure of this new protein-lipid complex, demonstrating that this protein has a "pocket" which specifically recognizes the hydrophilic heads of some of the lipids that make up the cell membrane. Importantly, this "recognition pocket" is found not only in RVF virus but also in the envelope proteins of other viral families transmitted by arthropods, such as the dengue, Zika and chikungunya viruses, which have caused major worldwide epidemics in recent years.

In the homologous protein of the chikungunya virus, the scientists pinpointed one of the residues of the recognition pocket as amino acid 226. In 2006, the A226V mutation enabled chikungunya to be transmitted by a new species of mosquito that is prevalent on Reunion Island (Aedes albopictus, or the tiger mosquito).

"This study offers a further illustration of the power of comparative analyses of viruses that appear very distant, such as bunyaviruses, alphaviruses and flaviviruses, which can result in highly significant findings and reveal shared mechanisms of action," commented Félix Rey, Head of the Structural Virology Unit (Institut Pasteur/CNRS), where the study was carried out.

Understanding the mechanism used by these viruses for insertion in the cell membrane paves the way for the development of therapeutic agents that target the "pocket" involved in the fusion of viral and cell membranes with the aim of preventing pathogenic arboviruses from entering host cells.

Media Contact

Myriam Rebeyrotte / Aurélie Perthuison
presse@pasteur.fr

http://www.pasteur.fr 

Myriam Rebeyrotte / Aurélie Perthuison | EurekAlert!

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Global study of world's beaches shows threat to protected areas

19.07.2018 | Earth Sciences

New creepy, crawly search and rescue robot developed at Ben-Gurion U

19.07.2018 | Power and Electrical Engineering

Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says

19.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>