Scientists use light to control protein activity in living cells

Researchers at the University of North Carolina at Chapel Hill have developed a method which uses light to control protein activity inside live cells with the flick of a switch. According to the researchers, the technique, developed in the early 2000s, uses light to activate and deactivate proteins that could turn brain cells on and off. Additionally, the technique give them ideas of what individual brain circuits do and how they relate to different aspects of behavior and personality. However, it has had its limitations – only a few proteins could be controlled, the researchers claim.

According to the paper published in Science, the team expand optogenetics to control a wide range of proteins while their functions remain unaffected. These light-controllable proteins can be turned on almost anywhere in the cells, allowing the researchers to see how proteins carry out their functions depending on where they are turned on and off. For the study, the team used a computational approach to identify which parts of a protein could be altered while its functions are kept intact. They found that loops of protein structure commonly found on protein surfaces can be readily modified with different ‘knobs’ to control proteins with light, or even to respond to drugs.

The team also claim that the switch they developed is so versatile and fast that they can toggle a protein on or off as fast as they can toggle their light. And, they can control how much of a protein is activated or inactivated by changing the intensity of light. Furthermore, the technique allows the researchers to control how long proteins are activated at different points in the cell by controlling the timing of irradiation. This ability to manipulate proteins allows researchers to study proteins in living systems and wide range of diseases, which often result from the malfunctioning of a single protein.

Reference: Engineering extrinsic disorder to control protein activity in living cells – Science, AAAS