channelrhodopsin-2

ion channel

Also known as: ChR2

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Last updated

July 20, 2026

Quick Summary

Channelrhodopsin-2 (ChR2) is a light-sensitive protein that functions as an ion channel. When exposed to light, ChR2 allows positively charged ions to flow across the cell membrane, which can activate or inhibit the cell's electrical activity. This property makes it a valuable tool in optogenetics, a research method that uses light to control specific events within cells. By genetically targeting cells to produce ChR2, researchers can use light to precisely control neuronal activity in living animals, aiding in the study of brain function and behavior.

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Karl Deisseroth
…light-sensitive ion channel known as channelrhodopsin-2 (ChR2), which occurs naturally in algae, could act as an optical switch in mammalian neurons. The neurons, genetically engineered to express ChR2 on their surface, could be turned on when exposed to a flash of blue light, enabling very rapid and precise control over…
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…light-sensitive ion channel known as channelrhodopsin-2 (ChR2), which occurs naturally in algae, could act as an optical switch in mammalian neurons. The neurons, genetically engineered to express ChR2 on their surface, could be turned on when exposed to a flash of blue light, enabling very rapid and precise control over…
Read More