RT Journal Article
SR Electronic
T1 Anion-conducting channelrhodopsins with tuned spectra and modified kinetics engineered for optogenetic manipulation of behavior
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 156422
DO 10.1101/156422
A1 Jonas Wietek
A1 Silvia Rodriguez-Rozada
A1 Janine Tutas
A1 Federico Tenedini
A1 Christiane Grimm
A1 Thomas G. Oertner
A1 Peter Soba
A1 Peter Hegemann
A1 J. Simon Wiegert
YR 2017
UL http://biorxiv.org/content/early/2017/09/16/156422.abstract
AB Genetic engineering of natural light-gated ion channels has proven a powerful way to generate optogenetic tools for a wide variety of applications. In recent years, blue light-activated engineered anion conducting channelrhodopsins (eACRs) have been developed, improved, and were successfully applied in vivo. We asked whether the approaches used to create eACRs can be transferred to other well-characterized cation-conducting channelrhodopsins (CCRs) to obtain eACRs with a broad spectrum of biophysical properties. We generated 22 variants using two conversion strategies applied to 11 CCRs and screened them for membrane expression, photocurrents and anion selectivity. We obtained two novel eACRs, Phobos and Aurora, with blue-and red-shifted action spectra and photocurrents similar to existing eACRs. Furthermore, step-function mutations greatly enhanced the cellular operational light sensitivity due to a slowed-down photocycle. These bistable eACRs can be reversibly toggled between open and closed states with brief light pulses of different wavelengths. All new eACRs reliably inhibited action potential firing in pyramidal CA1 neurons. In Drosophila larvae, eACRs conveyed robust and specific light-dependent inhibition of locomotion and nociception.