Their findings, detailed in a paper in this week’s advance online issue of the journal Nature, could also shed light on the mystery of why some people with HIV never develop symptoms of AIDS. The biologists found that a gene called Human Schlafen 11 produces a protein that inhibits the replication of HIV in infected human cells by blocking the ability of the host cell to synthesize viral proteins.
“Some people with HIV develop AIDS rapidly and others can be HIV positive for decades and never really develop any symptoms of the disease,” said Michael David, a professor of biology at UC San Diego, who headed the research team. “It’s still unclear why that is, but one possibility is that the genetic variations in this protein, like in many other viral restriction factors, account for the differences in the susceptibility to the virus.”
Because Human Schlafen 11 specifically blocks synthesis of HIV proteins, the researchers are conducting further studies to see if variations in the Human Schlafen 11 gene can be correlated with disease progression in HIV infected individuals. If that turns out to be the case, the discovery could one day lead to the development of a diagnostic test for HIV infected individuals that would inform them of their likelihood of developing AIDS or, better yet, the development of a therapeutic drug that would prevent HIV infected individuals from ever developing AIDS.
“If it’s possible for the human cell to inhibit the synthesis of viral programs without affecting the synthesis of cellular proteins, it’s possible that at some point a drug can do that, too,” said David. “But our discovery is just the tip of the iceberg. There’s a lot more work to be done. Whether this will have diagnostic or therapeutic value remains to be seen.”
Human Schlafen 11 is member of a family of six genes in humans and nine genes in mice that are induced in mammalian cells in response to various kinds of infection, specifically infections that result in the release of anti-viral proteins called interferons. The first Schlafen gene was discovered in mice at UC San Diego in 1998 by Steve Hedrick, a professor of biology.
David said his laboratory had spent the past eight years trying to figure out what role Human Schlafen 11 plays in human cells before discovering its unique role. He added that they were intrigued when Manqing Li, a project scientist in the lab, discovered that the Human Schlafen 11 protein was missing in a cell line used to produce large amounts of virus in the laboratory. “When we put Schlafen 11 back into the cell line, we got over 90 percent inhibition of virus output,” David said, confirming that the gene was critical to inhibiting virus replication.
David said that while Schlafen genes have been known for many years, his laboratory’s discovery is the first to shed light on how they work at the molecular level. His team is now collaborating with several groups to determine if other Human Schlafen genes have an anti-viral effect against other viruses, such as those that cause influenza and dengue fever.
The researchers are also collaborating with scientists who oversee tissue banks containing DNA samples from thousands of individuals infected with HIV to determine whether variations in the genetic sequences of the Human Schlafen 11 gene can be correlated with the development of clinical symptoms in those individuals. David’s team is part of a collaboration called HIV Immune Networks Team or HINT (http://hint.org/), which is funded by NIAID at the National Institutes of Health to “use systems biology approaches to reveal how the early immune response defends against HIV-1 infection with a view toward blocking virus.”
UC San Diego biologists Manqing Li, Elaine Kao, Xia Gao and Hilary Sandig in David’s laboratory worked on the experiments that led to the discovery. Other co-authors of the paper included Mariana Pavon-Eternod, Thomas Jones and Tao Pan of the University of Chicago; and Sebastien Landry and Matthew Weitzman of The Salk Institute for Biological Studies.
The research was supported by grants from the National Institutes of Health (AI81019, AI074967, P01AI090935, R01GM101982 and R21AI088490). Anyone interested in licensing this technology should contact the UC San Diego Technology Transfer office at email@example.com
| Newswise Science News
Transport of molecular motors into cilia
28.03.2017 | Aarhus University
Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Life Sciences
28.03.2017 | Information Technology
28.03.2017 | Physics and Astronomy