Anion-conducting channelrhodopsins are used as tools to manipulate brain activity in mice, fruit flies and other model organisms (Optogenetics).
Neurons expressing anion-conducting channelrhodopsins are silenced when illuminated with light, an effect that has been used to investigate information processing in the brain.
Naturally occurring anion-conducting channelrhodopsins (ACRs) were subsequently identified in cryptophyte algae.
When expressed in nerve cells, ACRs act as light-gated chloride channels.
[22] To inhibit neurons with wide-field illumination, it has proven useful to restrict ACRs to the somatic compartment (ST variants).