Channelrhodopsin-1 (ChR1) and Channelrhodopsin-2 (ChR2) from the model organism Chlamydomonas reinhardtii are the first discovered channelrhodopsins. Variants that are sensitive to different colors of light or selective for specific ions (ACRs, KCRs) have been cloned from other species of algae and protists .

Channelrhodopsins (ChRs) are light-activated channels from algae that provide these organisms with fast sensors to visible light for phototaxis. Since its discovery, Channelrhodopsin 2 (ChR2) has been utilised as a research tool to depolarise membranes of excitable cells with light.

The light-gated cation channel Channelrhodopsin-2 (ChR2) is a powerful and versatile tool for controlling neuronal activity. Currently available versions of ChR2 either distribute uniformly throughout the plasma membrane or are localised ...

The introduction of Channelrhodopsin (ChR2) from the green alga Chlamydomonas reinhardtii has sparked excitement not only in the neurons that express it, but also in many neuroscientists. ChR2 is a light-gated cation channel that activates neurons in …

Channelrhodopsin2 is a photoactivatable long stokes shift fluorescent protein published in 2003, derived from Chlamydomonas reinhardtii. It has high acid sensitivity.

ChR2, a directly light-gated cation channel of the green algae Chlamydomonas reinhardtii, allows depolarizing and firing neurons with brief blue light pulses (1, 2). Because the single channel conductance of ChR2 is very small, high expression levels are required to fire neurons reliably.

Nov 24, 2017 · The light-gated ion channel channelrhodopsin 2 (ChR2) from Chlamydomonas reinhardtii is a major optogenetic tool. Photon absorption starts a well-characterized photocycle, but the structural basis ...

A microbial type rhodopsin, ChR2 is a directly light-switched cation-selective ion channel. This channel opens rapidly after absorption of a photon to generate a large permeability for monovalent and divalent cations. ChR2 desensitizes in …

Sep 15, 2017 · Channelrhodopsins (ChRs) are naturally occurring light-gated ion channels that are important for allowing motile algal cells to find suitable light levels. In neuroscience, ChRs have become broadly significant for helping to enable the control of specific circuit elements with light (i.e., optogenetics).

Feb 13, 2025 · Channelrhodopsin-2 (ChR2) has a retinal as the chromophore group and is activated by blue light at around 470 nm with conformational change from the closed (ground state) to the open state and permeates cations, especially Na + ions.