Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

2-way cell talk provides clues about neuromuscular disease

19.02.2008
It’s a scientific given that neurons tell other cells what to do, but new evidence suggests that, like with any good relationship, these target cells also have much to contribute, scientists say.

In an animal model, Medical College of Georgia researchers have shown that if a muscle cell fails to produce the protein beta-catenin, its neuron doesn’t develop or function properly.

Their finding provides some of the first proof that in vertebrates such as man, this retrograde communication – from the target cell back to the neuron – is essential, says Dr. Lin Mei, corresponding author on research published online Feb. 17 in Nature Neuroscience.

“Previously, we thought signals flow mainly from neuron to muscle. This shows they can be produced from muscle,” says Dr. Mei, MCG’s chief of developmental neurobiology and Georgia Research Alliance Eminent Scholar in Neuroscience. “This is some of the first clear genetic evidence that when you disturb something in the muscle, you have a nerve problem.”

Dr. Mei’s research team knocked out beta-catenin in the muscle cells of a developing mouse. As a result, nerve terminals, which reach out to target cells, were misaligned. Release of neurotransmitters, which enable cell talk, from the tiny vesicles inside nerve terminals was impaired. Mice died prematurely. “Two-way communication is absolutely essential,” he says. Interestingly when the researchers knocked beta-catenin out of neurons instead, neurons developed and functioned normally.

“Theoretically the finding is very important in that it supports the retrograde hypothesis,” Dr. Mei says. “Practically it is also important because problems with motor neuron survival and differentiation cause many neuromuscular diseases, such as muscular dystrophy and ALS, where motor neurons need to survive,” noting that it’s unknown why neurons die in these diseases.

“We believe there is a retrograde signal downstream of beta-catenin or regulated by beta- catenin,” says Dr. Mei. “If you don’t have beta-catenin in the muscle, that signal may be missing and motor neurons are not happy.”

To find out what that signal is, his lab is comparing genetic expression in the beta-catenin knockout mouse to that of a normal mouse to see which genes are up- or down-regulated. “Those genes may be targeted by beta-catenin and may serve as this retrograde signal. If we can identify that, I can retire,” says Dr. Mei.

Beta-catenin is a protein with many roles, including helping cells stick together, and regulating gene expression in the Wnt pathway, which is essential for development. Dr. Mei’s previous work has shown that at least in a Petri dish, when a signaling component of the Wnt pathway, called disheveled, is disturbed in muscle cells, it causes problems with their co-cultured neurons.

In the early 1900s, German-born Scientist Viktor Hamburger provided some of the first evidence of the importance of retrograde communication in proper development of motor neurons: when he removed the budding limbs of chick embryos, motor neurons decreased in number.

“ … (T)he use of transgenic animals has established the importance of muscle ß-catenin in (neuromuscular junction) formation in vivo,” write Drs. Amy K.Y. Fu, Zelda Cheung and Nancy Y. Ip, of Hong Kong University of Science and Technology in an accompanying News and Views. “These findings also underscore the emerging role of Wnt signaling proteins in the regulation of synapse development. The identification of muscle ß-catenin-dependent signals for motoneurons may also contribute to our understanding of neuromuscular disorders, including muscular dystrophy and amyotrophic lateral sclerosis.”

Toni Baker | EurekAlert!
Further information:
http://www.mcg.edu

Further reports about: Beta-Catenin Disease Neuron neuromuscular retrograde

More articles from Life Sciences:

nachricht New photocatalyst speeds up the conversion of carbon dioxide into chemical resources
29.05.2017 | DGIST (Daegu Gyeongbuk Institute of Science and Technology)

nachricht Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>