Optogenetics: from curiosity about an alga to Nobel potential for Deisseroth

This story started with a simple question. German scientist Peter Hegemann wanted to discover how a single-celled algae always swims towards light. The response sparked a revolution. Almost 30 years ago, Hegemann and his colleague Georg Nagel discovered a light-sensitive protein in algae.

Then the American Karl Deisseroth applied the discovery to rat brains. He introduced this protein into neurons that also became reactive to light. By illuminating these neurons with an optical fiber inserted into the skull, it triggered a reaction: the movement of the mouse's whiskers. Optogenetics was born.

Since ancient times, researchers have tried to understand how the brain stores memories and develops feelings and behaviors, but they were unable to show exactly which type of cell was acting, only regions of the brain.

Optogenetics has revolutionized neuroscience by shining light on microparts of the brain. Scientists have created a kind of switch that turns specific nerve cells on and off. With the technique, they can provoke or inhibit neurons very precisely and this allows them to directly test what happens when a neuron is activated or silenced.

Researchers were able to trigger memory neurons in mice. Now, optogenetics has begun to be investigated in medical applications to study psychiatric disorders, for example. According to the Nobel Committee, it is being used in studies that seek to restore vision to blind people.

Over the phone, Hegemann recalled that a simple curiosity about algae caused this revolution. Therefore, young scientists must remain curious and, above all, work on something new.

This Monday (5), Deisseroth was welcomed with a party at the laboratory at Stanford University, in California. He said he received a call from the Nobel Prize committee shortly after midnight: