Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'Good' prion-like proteins boost immune response

09.08.2011
A person's ability to battle viruses at the cellular level remarkably resembles the way deadly infectious agents called prions misfold and cluster native proteins to cause disease, UT Southwestern Medical Center researchers report.

This study marks the first discovery of so-called "good" prion-like proteins in human cells and the first to find such proteins involved in innate immunity: the way the body recognizes and responds to threats from viruses or other external agents, said Dr. Zhijian "James" Chen, professor of molecular biology and senior author of the study in the Aug. 5 print edition of the journal Cell.

"An understanding of how cells maintain good prion-like proteins called MAVS [mitochondrial antiviral signaling] protein may help us understand how some prions turn bad," said Dr. Chen, a Howard Hughes Medical Institute investigator at UT Southwestern. Moreover, the research may also deepen our knowledge of innate immunity and host defense, he said.

Prions are misfolded, self-perpetuating proteins responsible for fatal brain infections such as bovine spongiform encephalopathy – so-called mad cow disease – in cattle and the extremely rare variant Creutzfeldt-Jakob Disease (vCJD) in some people who eat beef from infected cattle. Currently all prion-related diseases are untreatable and are fatal.

The MAVS prion-like proteins usually are scattered on the membranes of the energy-producing organelles called the mitochondria that reside inside cells throughout the body, he explained.

UT Southwestern researchers, investigating the cellular response to invasion by a member of the family of viruses that includes influenza and hepatitis, discovered that the MAVS proteins change shape and recruit other MAVS proteins to misfold and aggregate [cluster] in tough clumps on the surface of the mitochondrial membranes to defend against viral assault, Dr. Chen said.

The researchers created a setup that mimicked the human immune response, but in a controlled laboratory environment where they were able to break open cells and study the cellular components. When those components were mixed with viral RNA (the genetic material also known as ribonucleic acid), the MAVS proteins still formed large clusters.

"Remarkably, the MAVS proteins behave like prions and effectively convert nearby proteins into aggregates on the mitochondrial membrane," Dr. Chen said. He noted that the aggregates are necessary for the cells to churn out immunity-boosting interferon molecules. When the MAVS activity is blocked, the antiviral defense stops.

The MAVS' prion-like mechanism gives no indication of the out-of-control replication seen in disease-causing prions, Dr. Chen said, providing an intriguing area for future research.

Other UT Southwestern researchers involved in the study were lead author Dr. Fajian Hou, instructor of molecular biology; Dr. Lijun Sun, assistant professor of molecular biology and an HHMI research specialist; Dr. Hui Zheng, postdoctoral fellow in cell biology; Brian Skaug, a student in the medical scientist training program; and Dr. Qui-Xing Jiang, assistant professor of cell biology.

The study was funded by grants from the National Institutes of Health and the Welch Foundation.

This news release is available on our World Wide Web home page at http://www.utsouthwestern.edu/home/news/index.html

To automatically receive news releases from UT Southwestern via email, subscribe at www.utsouthwestern.edu/receivenews

Deborah Wormser | EurekAlert!
Further information:
http://www.utsouthwestern.edu

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>