# Optogenetic Manipulation Of Neural Activity In Freely Moving Caenorhabditis elegans

 Title: Optogenetic Manipulation Of Neural Activity In Freely Moving Caenorhabditis elegans Author: Samuel, Aravinthan DT; Leifer, Andrew M.; Fang-Yen, Christopher; Gershow, Marc; Alkema, Mark Note: Order does not necessarily reflect citation order of authors. Citation: Leifer, Andrew M., Christopher Fang-Yen, Marc Gershow, Mark Alkema, and Aravinthan D. T. Samuel. 2011. Optogenetic manipulation of neural activity in freely moving Caenorhabditis elegans. Nature Methods 8, no. 2: 147-152. Full Text & Related Files: Leifer_Optogenetic.pdf (180.4Kb; PDF) Abstract: We present an optogenetic illumination system that is capable of real-time light delivery with high spatial resolution to specified cellular targets in freely moving C. elegans. In our system, a tracking microscope and high-speed video camera records the posture and motion of an unrestrained worm expressing Channelrhodopsin-2 or Halorhodopsin/NpHR in specific cell types. Custom image processing software analyzes the position of a worm within each video frame, and then rapidly estimates the locations of targeted cells. The software then instructs a digital micromirror device to illuminate targeted cells with laser light of the appropriate wavelengths to stimulate or inhibit activity. Since each cell in an unrestrained worm is a rapidly moving target, our imaging and analysis system operates at high speed $$(\sim 50$$ frames per second) to provide high spatial resolution $$(\sim 30 \mu m)$$. To demonstrate the accuracy, flexibility, and utility of our system, we present optogenetic analyses of the worm motor circuit, egg-laying circuit, and mechanosensory circuits that were not possible with previous methods. Published Version: doi:10.1038/nmeth.1554 Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:8979495

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Peer reviewed scholarly articles from the Faculty of Arts and Sciences of Harvard University