Optogenetics (noun, “OP-toe-gen-EH-ticks”)
Optogenetics is a technique that can control a cell’s activity with light. It uses a molecule called channelrhodopsin (CHAN-el-roh-DOHP-sin). This molecule is found naturally in algae. It sits in a cell membrane. There, it acts like a gate, letting charged particles in or out. That rush of particles can make a cell pass messages to other cells. A channelrhodopsin opens in response to light. It can turn a cell’s activity up when the light turns on. In algae, the channel serves as a way to sense light.
Scientists can insert the genetic instructions for a channelrhodopsin into a cell they want to control. The cell then makes the channelrhodopsin molecule. It then inserts it into its own cell membrane. When scientists shine a light nearby, the channelrhodopsin opens. That lets particles rush in or out.
Scientists now use optogenetics to control how cells function in the brains of mice, rats and monkeys. This helps the researchers better understand how the cells work. Scientists have been able to use this technique to show how the brain controls hunger. It has also let them learn how the tongue tastes the “flavor” of water.
In a sentence
Scientists are also trying optogenetics in other organs — such as the heart.