Reporting in the April issue of the Journal of Virology, the researchers have identified a protein that plays an important role in the ability of the vesicular stomatitis virus (VSV) to invade healthy cells and reproduce itself. The finding could play a role in vaccine development and also help scientists develop anti-viral agents to stop similar viruses in their tracks.
Although VSV infects animals, it is not a human pathogen. Nevertheless, scientists study it because of its similarity to viruses such as Ebola and Marburg hemorrhagic fever viruses, as well as rabies virus. "VSV is a good model of a variety of other viruses," said John Connor, Ph.D., a research assistant professor of biochemistry. "Our research has given us a better understanding of how viruses like these are able to do the nasty things they do."
The scientists set out to study the role of a protein known as "matrix," which is produced by VSV. They suspected matrix was important in how VSV is assembled, but unexpectedly discovered the matrix protein is critical in how the virus reproduces and spreads. When they altered the matrix protein, they weakened the virus’ ability to reproduce. The finding has several important implications, Connor said.
Normally, VSV is extremely powerful, with the ability to shut down a cell’s system for making proteins. VSV then takes over the cell’s protein-making machinery and makes its own proteins so it can replicate and spread. The scientists were able to weaken this power by altering the matrix protein, so that VSV cannot make as much protein and does not reproduce as well.
Weakened viruses such as this are often used to make vaccines because they are less likely to be harmful. Currently, another weakened form of VSV is being used for a HIV vaccine that is being tested in humans. To make the vaccine, scientists started with the weakened VSV virus and added a protein from the HIV virus so that VSV "expresses" or makes a fragment of the HIV virus. In theory, when people are inoculated with the vaccine, they will develop antibodies to the HIV protein, and if they are exposed to the actual HIV virus, their bodies will neutralize it and kill it before it infects them.
In all, several weakened forms of VSV have been developed and at least two are currently being tested in HIV vaccines. If they don’t prove effective, vaccine developers can turn to one of the others, including the mutant VSV virus developed by Connor and colleagues.
"Right now, there’s no way of knowing which way of weakening the virus will make the best vaccine," Connor said.
In addition to its potential for vaccine development, the new finding about VSV also provides basic information about how the virus shuts downs a cell’s protein making-abilities and dominates the process.
"We always knew this happened, but the process was like a black box," said Connor. "Now, we know that the matrix protein is involved and is incredibly important in virus reproduction. This pushes forward our knowledge of how this virus is so effective at replicating."
Could the finding about matrix be used to weaken other types of viruses? The scientists aren’t sure, yet. "It’s a strong possibility that every virus will have an Achilles’ heel like this, where they need the function of a viral protein to make lots of virus," said Connor.
Karen Richardson | EurekAlert!
Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden
The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy