Optogenetic inhibition of the electrical activity of neurons enables the causal assessment of their contributions to brain functions. Red light penetrates deeper into tissue than other visible wavelengths. We present a red-shifted cruxhalorhodopsin, Jaws, derived from Haloarcula (Halobacterium) salinarum (strain Shark) and engineered to result in red light-induced photocurrents three times those of earlier silencers. Jaws exhibits robust inhibition of sensory-evoked neural activity in the cortex and results in strong light responses when used in retinas of retinitis pigmentosa model mice. We also demonstrate that Jaws can noninvasively mediate transcranial optical inhibition of neurons deep in the brains of awake mice. The noninvasive optogenetic inhibition opened up by Jaws enables a variety of important neuroscience experiments and offers a powerful general-use chloride pump for basic and applied neuroscience.
Bibliographical noteFunding Information:
We thank J. Juettner for help making AAV, and Y.K. Cho, D. Schmidt, F. Chen, A. Beyeler, J.M. Zhuo and R.E. Kohman for advice and discussion. A.S.C. acknowledges the Janet and Sheldon Razin ′59 Fellowship of the Massachusetts Institute of Technology (MIT) McGovern Institute. E.S.B. acknowledges Jerry and Marge Burnett, the US Defense Advanced Research Projects Agency Living Foundries Program HR0011-12-C-0068, Harvard/MIT Joint Grants Program in Basic Neuroscience, Human Frontiers Science Program, Institution of Engineering and Technology A F Harvey Prize, MIT McGovern Institute and McGovern Institute Neurotechnology (MINT) Program, MIT Media Lab, New York Stem Cell Foundation-Robertson Investigator Award, US National Institutes of Health (NIH) Director’s New Innovator award 1DP2OD002002, NIH EUREKA award 1R01NS075421, NIH grants 1R01DA029639, 1RC1MH088182
and 1R01NS067199, US National Science Foundation (NSF) CAREER award CBET 1053233 and NSF grants EFRI0835878 and DMS0848804, the Skolkovo Institute of Science and Technology, a Society for Neuroscience Research Award for Innovation in Neuroscience (RAIN) and the Wallace H. Coulter Foundation. M.L.M. acknowledges funding from NSF DGE 1122492. J.A.C. acknowledges funding from the Whitehall Foundation, the Klingenstein Foundation, the Swebelius Family Trust, the Simons Foundation, an Alfred P. Sloan Fellowship, a NARSAD Young Investigator Award, a Smith Family Award for Excellence in Biomedical Research, NIH R00 EY018407, NIH R01 EY022951 and NIH R01 MH102365. V.B. acknowledges Human Frontier Science Program, Swiss National Science Foundation and Volkswagen Foundation fellowships. B.R. acknowledges the Gebert-Ruf Foundation, SNSF, European Research Council, and European Union SEEBETTER, TREATRUSH, OPTONEURO and 3X3D Imaging grants. X.H. acknowledges funding from an NIH Director’s New Innovator Award (1DP2NS082126), the NINDS (1R01NS087950, 1R21NS078660, 1R01NS081716), NIMH (5R00MH085944), Pew Foundation, Alfred P. Sloan Foundation, Michael J. Fox Foundation, and Brain and Research Foundation. Y.L. acknowledges funding from NIH RO1 MH091220-01. B.Y.C. acknowledges funding from US Defense Advanced Research Projects Agency Living Foundries, the US National Science Foundation Biophotonics and the Brain Research Foundation. K.M.T. acknowledges funding from the Whitehall Foundation, Klingenstein Foundation, JPB Foundation, PIIF Funding, R01-MH102441-01 (NIMH) and DP2-OD-017366-01. G.A.C.M. was supported by the Simons Center for the Social Brain.