Ed Boyden’s group has published High-performance genetically targetable optical neural silencing by light-driven proton pumps, detailing a set of new optical neuronal off-switches borrowed from various species that appear to be much better than Halorhodopsin for silencing neurons. Halo works well for preventing action potentials when the nucleus is illuminated, but has a harder time blocking transmission of action potentials down an axon after it has been initiated. Also, previously engineered Halo variants, including eNpHR, suffer from light-dependent inactivation and have an expression sweet spot that could use broadening. I’m looking forward to finding out if Arch, and the other new switches from Boyden’s group allow more powerful experiments in our hands.
A Better Neuronal Off-Switch13 01 2010