3.E.1.7.8
Light-activated cation selective ion channel [synthetic construct] of 344 aas and 7 probable TMSs. It is also called ComV1 or Ex3mV1Co. Channelrhodopsins have been utilized in gene therapy to restore vision in patients with retinitis pigmentosa (Hatakeyama et al. 2023). Channel kinetics (tauon and tauoff) were considerably altered by the replacement of the 172nd amino acid and was dependent on the amino acid characteristics. The size of amino acids at this position correlated with tauon and decay, whereas the solubility correlated with tauon and tauoff. Molecular dynamic simulation indicated that the ion tunnel constructed by H172, E121, and R306 widened due to H172A variant, whereas the interaction between A172 and the surrounding amino acids weakened compared with H172. The bottleneck radius of the ion gate constructed with the 172nd amino acid affected the photocurrent and channel kinetics. The 172nd amino acid in ComV1 is a key residue for determining channel kinetics as its properties alter the radius of the ion gate (Hatakeyama et al. 2023).