High-efficiency channelrhodopsins for fast neuronal stimulation at low light levels.

ABSTRACT: Channelrhodopsin-2 (ChR2) has become an indispensable tool in neuroscience, allowing precise induction of action potentials with short light pulses. A limiting factor for many optophysiological experiments is the relatively small photocurrent induced by ChR2. We screened a large number of ChR2 point mutants and discovered a dramatic increase in photocurrent amplitude after threonine-to-cysteine substitution at position 159. When we tested the T159C mutant in hippocampal pyramidal neurons, action potentials could be induced at very low light intensities, where currently available channelrhodopsins were unable to drive spiking. Biophysical characterization revealed that the kinetics of most ChR2 variants slows down considerably at depolarized membrane potentials. We show that the recently pu

SUBMITTER: Berndt A 

PROVIDER: S-EPMC3088623 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature