Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

HIV eludes body’s smart bomb

08.07.2003


HIV inactivates the body’s cellular smart bomb



HIV eludes one of the body’s key smart bomb defenses against infection, and this finding may lay the groundwork for new drugs to treat AIDS, according to a new Salk Institute study.

Nathaniel Landau, a Salk Institute associate professor, and his team have pinpointed how the body battles HIV, a tremendously complex and relentless virus. Their findings appear in the online issue of Cell and will be published in the July 11 print issue.


"What we have uncovered is a war that is being fought on the molecular level between viruses and cells. The war has been going on for millions of years, but we didn’t know about it until now," said Landau.

"We have been focusing on an antiviral system that we never knew about-a single protein called APOBEC3G. APOBEC3G would be a powerful inhibitor of viruses such as HIV, except for one problem: the virus has outsmarted it. During the evolutionary war between the virus and the host, the virus developed an effective counter-measure."

That counter-measure is a gene in HIV called virion infectivity factor (Vif). In an HIV-infected cell, according to Landau, Vif molecules are produced and then attach to the APOBEC3G protein molecules. Once attached, Vif prevents APOBEC3G from getting into the new viruses, and these viruses go on to replicate and spread throughout the body.

Having identified the interaction between Vif and APOBEC3G, Landau and his team then focused on a fundamental question: would it be possible to beat the virus at its own game?

"We found that mice also have the antiviral protein," said Landau. "But interestingly, HIV can’t recognize the mouse protein. As a result, mouse APOBEC3G is a powerful blocker of HIV replication. The mouse APOBEC3G protein goes into HIV and Vif can’t kick it out."

The mouse APOBEC3G functions like a smart bomb with a time-delayed fuse. When the virus is produced in an infected cell, APOBEC3G molecules get into the virus. At first, the protein does nothing; however, when the virus infects a new cell, APOBEC3G is activated. As HIV begins to copy its genes into DNA, APOBEC3G attacks the virus, creating massive mutations. APOBEC3G attacks the cytosines in the virus DNA, removing an essential chemical group to make them into uracil. The viral DNA is so badly mutated that the viral genes can’t function.

"Drug companies may be able to use this information to design a novel type of drug to treat HIV infection. They could develop drugs that attach to APOBEC3G, physically blocking Vif from attaching. If Vif can’t bind to APOBEC3G, the process of HIV replication could be halted," said Landau.

The lead author of the paper was Roberto Mariani, a staff scientist at the Salk Institute. Co-authors of the paper include Darlene Chen, Bärbel Schröfelbauer, Francisco Navarro, Renate König, Brooke Bollman, Carsten Münk, Henrietta and Nymark-McMahon, all of the Salk Institute. The study was funded by the National Institutes of Health, the Elizabeth Glaser Pediatric AIDS Foundation and Concerned Parents for AIDS Research.


The Salk Institute for Biological Studies, located in La Jolla, Calif., is an independent nonprofit organization dedicated to fundamental discoveries in the life sciences, the improvement of human health and conditions, and the training of future generations of researchers. Jonas Salk, M.D., founded the institute in 1960 with a gift of land from the City of San Diego and the financial support of the March of Dimes Birth Defects Foundation.

Robert Bradford | EurekAlert!
Further information:
http://www.salk.edu/

More articles from Health and Medicine:

nachricht Why might reading make myopic?
18.07.2018 | Universitätsklinikum Tübingen

nachricht Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University

All articles from Health and Medicine >>>

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

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>