Scientists Use Fish To Track Neurons' Effects On Motion

September 21, 2009

Release from: Jamie Applegate
Daily Californian

A tiny fish has recently led to a big discovery that could have implications on how motion is studied.

UC Berkeley researchers working in conjunction with researchers from UC San Francisco recently published a study observing larval zebrafish in which they said they have found a new approach to studying how neurons influence motion.

The study, published in the Sept. 17 issue of Nature magazine, detailed how researchers used light to activate specific neurons in zebrafish spinal cords, linking those neurons to the fishes' motion.

"Our study is novel because it revealed a function that we didn't know at all about," said Claire Wyart, a post-doctoral fellow at the campus's department of molecular and cell biology and a co-author of the study with molecular and cell biology professor Ehud Isacoff.

The study could have far-reaching implications for the medical community, Wyart said.

"Cerebrospinal fluid-contacting neurons are also present in humans," she said. "Our results in fish raise the question whether they could be important for locomotion in humans as well."

The researchers said that they employed novel methods to reach their conclusions. Using light, they discovered they can remotely activate the neuron and examine the behavior it controls.

According to Wyart, the neurons are known as the Kolmer-Agduhr neurons in zebrafish. They were first observed more than 75 years ago but their function has since remained unknown, until now.

When Wyart flashed the light on these cells, she observed that the fish started swimming slowly, linking the light to the fishes' motion.

The idea of being able to study and manipulate individual neurons could influence medical treatments of neurological diseases, said Mu-ming Poo, a professor of neurobiology at UC Berkeley.

"(The study's) importance is in its novel approach in studying the behavior of individual neurons," he said. "Using this method, we could be able to selectively stimulate or inhibit cells. In principle, this could be used to cure neurological diseases."

He said that the method used could also be important because it is non-invasive and could even have implications for people with Parkinson's disease.

"It's a good example of how we can use optical methods instead of electrical methods to stimulate the brain," he added.