Navigation Links
Scientists post lower speed limit for cell-signaling protein assembly
Date:7/29/2010

EAST LANSING, Mich. The apparently random self-assembly of molecular threads into the proteins that make the body work is far less frantic than previously thought, Michigan State University scientists say. That discovery could be a key to help unlock the nature of some diseases.

How proteins spontaneously "fold" from wiggling chains of amino acids into a wide variety of functional or malfunctioning three-dimensional molecules is one of the biggest mysteries in biochemistry.

"People thought they understood how protein diffusion worked, but now our data suggests they're wrong by a factor of 1,000," MSU physics and astronomy assistant professor Lisa Lapidus said. "Now we can start changing the models we've been trying to solve protein folding for 50 years, and now we're advancing our fundamental understanding of what unfolded proteins do before they fold."

The findings were published online by the science journal Proceedings of the National Academy of Sciences. Lapidus was joined in the research by University of Zurich Institute of Physical Chemistry researcher Steven Waldauer, whose recent MSU doctoral dissertation formed the basis of the study, and University of California, Davis, scientist Olgica Bakajin.

Proteins, which do most of the work in the body's cells, are chain molecules composed of amino acids. The order in which the amino acids are assembled was charted by the Human Genome Project, but the function of the protein depends on its shape, and how a protein folds is not yet understood. Much of the process is random and diffusive, like sugar moving through an unstirred cup of coffee.

Most proteins can fold in milliseconds, although there are so many possible combinations that left to chance it's physically impossible, scientists agree. So they speculate that there must be built-in folding pathways but those remain unproved. Now physics is helping make sense of biology, posting a lower speed limit for proteins as they spontaneously assemble into their lowest-energy, so-called natural state like a relaxed spring.

"In order to measure how quickly this random, unfolded state changes confirmations, we had to design an entirely new apparatus as well as design and fabricate a microfluidic chip capable of observing proteins within a fraction of a millisecond after being allowed to refold," Waldauer explained. Two lasers were employed to observe the formation of the immunoglobulin proteins.

"We found that the nature of the unfolded state is far from intuitive and that a protein will change from one random conformation to another much more slowly than previously thought," he said.

Scientists know that errors can occur in folding, and these are associated with a variety of diseases including Alzheimer's, ALS, cystic fibrosis and diabetes. Lapidus and colleagues speculate that the rate of the process could influence the outcome. Proteins that wiggle more rapidly, for example, may be more prone to sticking together and causing plaques such as those in Alzheimer's. The team's discovery may lead to new therapeutic strategies for this class of diseases.

"I believe this measurement of intramolecular diffusion is something that will be crucial for any subsequent studies of protein folding or mis-folding," Lapidus said.


'/>"/>

Contact: Mark Fellows
mark.fellows@ur.msu.edu
517-884-0166
Michigan State University
Source:Eurekalert  

Related biology news :

1. Jefferson scientists deliver toxic genes to effectively kill pancreatic cancer cells
2. Scientists identify novel inhibitor of human microRNA
3. Argonne scientists peer into heart of compound that may detect chemical, biological weapons
4. MU scientists go green with gold, distribute environmentally friendly nanoparticles
5. Scientists identify gene that may contribute to improved rice yield
6. Scientists discover why a mothers high-fat diet contributes to obesity in her children
7. MU scientists see how HIV matures into an infection
8. Earth scientists keep an eye on Texas
9. Thinking it through: Scientists call for policy to guide biofuels industry toward sustainability
10. Scientists identify a molecule that coordinates the movement of cells
11. Scientists Find new migratory patterns for Mediterranean and Western Atlantic bluefin tuna
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Scientists post lower speed limit for cell-signaling protein assembly
(Date:8/15/2017)... HAMPTON, Va. , Aug. 15 2017   ivWatch LLC ... effectiveness of intravenous (IV) therapy, today announced receipt of its ISO ... (QMS) developed by the International Organization for Standardization (ISO┬«). ... ivWatch Model 400 Continuous Monitoring device for ... "This ...
(Date:5/23/2017)... 2017  Hunova, the first robotic gym for the rehabilitation and functional ... in Genoa, Italy . The first 30 robots will ... USA . The technology was developed and patented at ... IIT spin-off Movendo Technology thanks to a 10 million euro investment from ... click: ...
(Date:4/19/2017)... New York , April 19, 2017 ... competitive, as its vendor landscape is marked by the ... the market is however held by five major players ... Safran. Together these companies accounted for nearly 61% of ... of the leading companies in the global military biometrics ...
Breaking Biology News(10 mins):
(Date:9/20/2017)... Palo Alto, CA (PRWEB) , ... September 20, ... ... and public interest organization focused on molecular manufacturing and other transformative technologies, announced ... categories, one for Experiment and the other for Theory in nanotechnology/molecular manufacturing. , ...
(Date:9/19/2017)... ... 19, 2017 , ... Participants of this educational webinar will ... Along with the advantages and disadvantages of ductless, filtered fume hoods, they will ... laboratory. , Attendees will learn from an industry expert about the different types ...
(Date:9/19/2017)... ... September 19, 2017 , ... The new and improved Oakton® pocket ... testers even stand upright with a new cap design that is versatile, functional and ... field who need to test water quality. , The Oakton pocket testers have many ...
(Date:9/19/2017)... (PRWEB) , ... September 19, 2017 , ... ... is pleased to announce the recipients of its 2017 Science Student Award. The ... leadership qualities, and involvement with community service defray the costs of obtaining their ...
Breaking Biology Technology: