Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Features of replication suggest viruses have common themes, vulnerabilities

14.08.2007
A study of the reproductive apparatus of a model virus is bolstering the idea that broad classes of viruses - including those that cause important human diseases such as AIDS, SARS and hepatitis C - have features in common that could eventually make them vulnerable to broad-spectrum antiviral agents.

In a study published today (Aug. 14) in the online, open-access journal Public Library of Science Biology, a team of researchers from the Howard Hughes Medical Institute (HHMI) at the University of Wisconsin-Madison describes in fine detail how an RNA virus known as flock house virus co-opts a cell's membranes to create an intracellular lair where it can safely replicate its genes.

The results provide strong evidence that at least some of the machinery four of the seven distinct classes of known viruses use to reproduce have common attributes. Such a discovery is important because it reveals a common viral theme that may be vulnerable to disruption and could lead to the development of drugs to treat many different kinds of viral infections, much like antibiotics are used to attack different kinds of bacterial pathogens.

"It turns out that viruses previously thought of as distinct share common features," says Paul Ahlquist, an HHMI investigator and virologist at UW-Madison. "We've found some features of replication that appear to cross over among many viruses."

Using powerful electron microscopy techniques, Ahlquist's group and their collaborators made the first three-dimensional maps of a viral replication complex using flock house virus, which, like all viruses, requires a host cell to make new genetic material and maintain the chain of infection.

In the case of flock house virus, the Wisconsin group found, the virus co-opts intracellular membranes of mitochondria, critical energy-regulating structures found in most eukaryotic cells.

Squeezing into the space between the inner and outer membrane of the double-lined mitochondria, the virus creates tens of thousands of protein-lined, balloon-like pockets where it can make new copies of the viral genome while safe from surveillance and defense mechanisms of the host.

" The virus has developed a very elegant strategy," says Ahlquist. "It creates for itself a new compartment for RNA synthesis, where it can collect its (constituent) components, organize successive steps of replication, and sequester these steps from other processes in the cell, most importantly, host defense responses."

In essence, the virus is reorganizing the cell to make a new intracellular architecture for its own purposes, according to Ahlquist. "The virus is reorganizing the cell to make a new organelle. It is a way to keep out competing processes and alarm-ringers and have a place where it can carry out its processes efficiently and for long periods of time."

The balloon-like sacs or spherules observed by Ahlquist and his colleagues all had narrow necks that transcended the membrane of the organelle to the cytoplasm, the medium inside the cell and in which the organelle is suspended. The neck is a gateway that appears to permit substrates needed for replication to enter and newly made viral genomes to exit.

The virus begins to co-opt the cell as a critical viral protein and viral RNA localize to the budding organelles, Ahlquist explains. "The virus takes over most of the available membrane. The protein creates a shell inside the spherule" to provide stability, and it is this use of a protein shell in replicating viral genes, the Wisconsin virologist suggests, that could be one of several common themes among different groups of viruses.

"Multiple features in the structure and function of these replication compartments appear similar across several virus classes," says Ahlquist. "This includes ways in which cell membranes are used to organize virus replication."

The shared features extend to most RNA viruses and a group known as reverse transcribing viruses, which include retroviruses such as HIV, suggesting a possible evolutionary link from a common ancestor.

Paul Ahlquist | EurekAlert!
Further information:
http://www.wisc.edu

More articles from Studies and Analyses:

nachricht WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf

nachricht First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>