Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New component of the ’brakes’ on nerve regeneration found

03.02.2005


Among the principal obstacles to regenerating spinal cord and brain cells after injury is the "braking" machinery in neurons that prevents regeneration. While peripheral nerves have no such machinery and can readily regenerate, central nervous system (CNS) neurons have their brakes firmly in place and locked.



Now, two groups of scientists have independently found a new component of that braking machinery, adding to understanding of the regulation of neuronal regeneration and of possible treatments to switch off the brakes on regrowth of spinal cord or brain tissue.

The two groups--one group led by Jong Bae Park, Glenn Yiu, and colleagues from Children’s Hospital Boston and the other led by Sha Mi and colleagues of Biogen Idec, Inc.--discovered that a protein variously called TAJ or TROY acts as an important part of the receptor on neurons that responds to growth-inhibitory molecules in myelin. Specifically, these molecules prevent the growth of the cablelike axons of injured neurons. Myelin is the fatty sheath that encases neurons and acts as an insulator and aid to the transmission of nerve impulses.


Researchers knew that CNS neurons had receptors on their surface that accepted the inhibitory molecules--like a key fitting a lock--and switched-on inhibitory signaling within the neuron. They had also shown that a protein called p75 could function as a component of the complex of proteins that make up this receptor. The puzzle, however, was that p75 is not widely made in the adult neurons in which this inhibitory receptor complex is known to function.

The two research groups turned their attention to TAJ/TROY because it is a member of the same family of receptor proteins--called TNF receptors--as p75. Their experiments revealed that TAJ/TROY is produced throughout the adult brains of mice. Also, they found that TAJ/TROY readily fits into the inhibitory receptor complex and that the resulting receptor complex switches-on the inhibitory machinery within neurons. Also, they found that treating neurons with a nonfunctional version of TAJ/TROY abolished neurons’ response to the "braking" molecules produced by myelin and encouraged neuron growth.

"Given the limited expression of p75, the discovery of TAJ function is an important step for understanding the regulation of axon regeneration," wrote Mi and colleagues.

Wrote Park and colleagues, "The implication that more than one TNF receptor member may be involved in myelin inhibition adds a new level of complexity to designing therapeutic strategies for treating CNS injury." They cited studies showing that TNF receptors are expressed in many types of cells in the CNS and are intimately involved in inflammatory responses that also play a role--perhaps harmful, perhaps beneficial to regeneration or recovery--in regulating response to injury. "Further characterization of the underlying mechanisms of these findings and their relation to myelin inhibition may provide important insights into designing therapeutic strategies to block myelin inhibition and cell death in the context of CNS injury," they wrote.

Heidi Hardman | EurekAlert!
Further information:
http://www.cell.com

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>