By studying nerve regeneration in roundworms, researchers in Japan have discovered another signaling pathway that induces nerves to regenerate.
Certain types of nerve injury, such as those from automobile accidents and falls, can damage or sever the axons that connect neurons and allow them to communicate with each other. Although axons elsewhere in the body can regenerate to some extent after such damage, those in nerves are far less capable, resulting in long-lasting or permanent impairment.
Treating such injuries requires clarification of how certain nerves are induced to regenerate and which molecular pathways are involved. By studying nerve regeneration in roundworms, Nagoya University researchers have discovered another signaling pathway that induces nerves to regenerate. The team also showed that this pathway is the same as the one that leads to identification and subsequent clearance of dying cells.
Neurons communicate with each other via electrical signals conveyed through dendrites and axons. This connectivity within the nerve is a source of the multiple functions of this organ, but damage to these connections due to trauma can cause functional impairment. Nerve regeneration after nerve injury is therefore an issue of special interest, but is difficult to study in humans. A non-parasitic, free-living roundworm nematode is a useful model for studying this issue as it avoids the ethical problems associated with human experimentation and its short generation time and simple development facilitate genetic engineering experiments.
To shed light on how damaged nerves are induced to regenerate, the researchers investigated various strains of this worm in which different genes were mutated or inactivated. They subjected the worms to a range of experiments, including labeling nerves with a fluorescent marker, cutting the nerves with a laser, and then monitoring their regrowth under a microscope.
They also examined the worms’ resistance with different genetic backgrounds to heavy metal stress, based on earlier findings that similar genes may be involved in both resistance to heavy metal exposure and nerve regeneration. When certain proteins encoded by these genes were absent or dysfunctional in the worms, their nerves were less able to regenerate, particularly during adulthood. They were also less able to endure exposure to a toxic level of copper.
By comparing these results among the strains in which single or multiple genes had been inactivated, the researchers established a complex molecular pathway that allows nerves to regenerate. They also found that the key molecular machinery involved in this is the same as that by which dying cells are recognized, engulfed by immune system cells, and disposed of.
“Many of the molecules and mechanisms we identified in worms have equivalents in humans,” corresponding author Naoki Hisamoto says. “Our findings should therefore lead us to targets in humans that we can use to improve recovery after nerve injury by promoting regrowth of damaged axons.”
The article “The Core Molecular Machinery Used for Engulfment of Apoptotic Cells Regulates the JNK Pathway Mediating Axon Regeneration in Caenorhabditis elegans” was published in The Journal of Neuroscience at doi: 10.1523/JNEUROSCI.0453-16.2016
This work was supported by the Ministry of Education, Culture and Science of Japan; MEXT (Grant-in-Aid for Scientific Research on Innovative Areas "Homeostatic regulation by various types of cell death," 15H01375); the Mitsubishi Foundation; the Naito Foundation; the Daiko Foundation; and the Astellas Foundation.
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences