TY  - JOUR
A1  - Bergs, Amelie
A1  - Schultheis, Christian
A1  - Fischer, Elisabeth
A1  - Tsunoda, Satoshi P.
A1  - Erbguth, Karen
A1  - Husson, Steven J.
A1  - Govorunova, Elena
A1  - Spudich, John Lee
A1  - Nagel, Georg
A1  - Gottschalk, Alexander
A1  - Liewald, Jana F.
T1  - Rhodopsin optogenetic toolbox v2.0 for light-sensitive excitation and inhibition in Caenorhabditis elegans
T2  - PLoS one
N2  - In optogenetics, rhodopsins were established as light-driven tools to manipulate neuronal activity. However, during long-term photostimulation using channelrhodopsin (ChR), desensitization can reduce effects. Furthermore, requirement for continuous presence of the chromophore all-trans retinal (ATR) in model systems lacking sufficient endogenous concentrations limits its applicability. We tested known, and engineered and characterized new variants of de- and hyperpolarizing rhodopsins in Caenorhabditis elegans. ChR2 variants combined previously described point mutations that may synergize to enable prolonged stimulation. Following brief light pulses ChR2(C128S;H134R) induced muscle activation for minutes or even for hours (‘Quint’: ChR2(C128S;L132C;H134R;D156A;T159C)), thus featuring longer open state lifetime than previously described variants. Furthermore, stability after ATR removal was increased compared to the step-function opsin ChR2(C128S). The double mutants C128S;H134R and H134R;D156C enabled increased effects during repetitive stimulation. We also tested new hyperpolarizers (ACR1, ACR2, ACR1(C102A), ZipACR). Particularly ACR1 and ACR2 showed strong effects in behavioral assays and very large currents with fast kinetics. In sum, we introduce highly light-sensitive optogenetic tools, bypassing previous shortcomings, and thus constituting new tools that feature high effectiveness and fast kinetics, allowing better repetitive stimulation or investigating prolonged neuronal activity states in C. elegans and, possibly, other systems.
KW  - Caenorhabditis elegans
KW  - Depolarization
KW  - Optogenetics
KW  - Light
KW  - Plasmid mapping
KW  - Muscle contraction
KW  - Cell membranes
KW  - Membrane potential
Y1  - 2018
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/45624
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-456242
SN  - 1932-6203
N1  - This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
VL  - 13
IS  - (2): e0191802
SP  - 1
EP  - 24
PB  - PLoS
CY  - Lawrence, Kan.
ER  -