Molecular shock absorbers buffer axonal tension of nerve cells
2nd Jun, 2020
Scientists have found out that spectrin, which are flexible rod-shaped molecules present in axons, act as ‘shock absorbers’ to protect axons from stretch-induced damage.
- Scientists have found out that spectrin, which are flexible rod-shaped molecules present in axons, act as ‘shock absorbers’ to protect axons from stretch-induced damage.
What are Axons?
- Axons are long tubular extensions of nerve cells that transmit electrical signals across long distances and can be up to a meter long in the case of humans.
- At such lengths, they are subjected to large stretch deformations during limb or other bodily movements.
- Axons in the brain too undergo significant deformations, even during normal activities like jumping (the human brain is as soft and wobbly as edible jelly).
Key-findings of the probe:
Probing into what special strategies axons adopt to protect themselves from damage during such stretch deformations, the scientists zeroed in on the molecule spectrin, a cytoskeletal protein.
- The neuronal cells may have evolved a clever strategy using an etched optical fiber attached to a piezo drive as a force-sensing cantilever to stretch live axons and to measure the resultant tension.
- Piezo drives attached to optical fiber is used to stretch on axons where optical fiber acts as a force-sensing cantilever.
- The resulting tension measured along the axon comes from the axonal cytoskeleton (consisting of biopolymers), of which spectrin is a part.
This study will have significant implications to our understanding of concussion that result from head impacts as well as stretch-induced nerve injuries.