Researchers identify key molecular step to fighting off viruses

Apr 21, 2010

UT Southwestern Medical Center researchers have determined how a protein that normally latches onto molecules inside cells and marks them for destruction also gives life to the body's immune response against viruses.

The researchers discovered that a certain form of the "death" ubiquitin interacts with another protein, called RIG-I, but does not mark it for destruction. Instead, this form of ubiquitin binds to and activates RIG-I, which is known to trigger the body's when a virus invades a cell.

Dr. Zhijian "James" Chen, professor of molecular biology at UT Southwestern, is senior author of the study, which is available online and in the journal Cell.

Dr. Chen and his colleagues reconstituted key elements of the human innate immune system in laboratory test tubes and found ubiquitin forms a unique chain-like structure that associates with RIG-I before RIG-I can get to work fighting viruses. The innate immune system is the body's first generic response against invading pathogens.

"Activation of RIG-I is the first line of our immune defenses against ," said Dr. Chen, an investigator for the Howard Hughes Medical Institute at UT Southwestern. "Understanding how it comes to life is a key step in developing new approaches to antiviral therapies. Having this test-tube system could help us identify substances that enhance the body's antiviral immunity."

Dr. Chen said his team's experiments mark the first time innate immunity has been recapitulated in a test tube. The findings provide one of the missing pieces in the complex puzzle of how the body fights off infection, he added.

Dr. Chen is now focusing on how activated RIG-I interacts with another protein called MAVS, also essential for .

Explore further: Owls and lizards lend their ears for human hearing research

Related Stories

Flick of a protein switches immune response

Jul 27, 2006

A single protein can turn on and off a key component of the immune system by changing partners in an elegant genomic dance, said researchers at the University of Southern California and Harvard Medical School.

Recommended for you

Owls and lizards lend their ears for human hearing research

3 hours ago

Lizards and owls are some of the animal species that can help us to better understand hearing loss in humans, according to new research out of York University's Department of Physics & Astronomy in the Faculty of Science.

Team finds key to tuberculosis resistance

8 hours ago

The cascade of events leading to bacterial infection and the immune response is mostly understood. However, the molecular mechanisms underlying the immune response to the bacteria that causes tuberculosis ...

Mutation may cause early loss of sperm supply

9 hours ago

Brown University biologists have determined how the loss of a gene in male mice results in the premature exhaustion of their fertility. Their fundamental new insights into the complex process of sperm generation ...

No more bleeding for 'iron overload' patients?

11 hours ago

Hemochromatosis (HH) is the most common genetic disorder in the western world, and yet is barely known. Only in the US 1 in 9 people carry the mutation (although not necessarily the disease).

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.