Optogenetic manipulation of neural activity in freely moving Caenorhabditis elegans

UMMS Affiliation

Department of Neurobiology; Alkema Lab

Publication Date


Document Type



Animals; Caenorhabditis elegans; *Movement; Muscle Cells; Neurons; *Optical Processes; Photobiology


Neuroscience and Neurobiology


We present an optogenetic illumination system capable of real-time light delivery with high spatial resolution to specified targets in freely moving Caenorhabditis elegans. A tracking microscope records the motion of an unrestrained worm expressing channelrhodopsin-2 or halorhodopsin in specific cell types. Image processing software analyzes the worm's position in each video frame, rapidly estimates the locations of targeted cells and instructs a digital micromirror device to illuminate targeted cells with laser light of the appropriate wavelengths to stimulate or inhibit activity. Because each cell in an unrestrained worm is a rapidly moving target, our system operates at high speed ( approximately 50 frames per second) to provide high spatial resolution ( approximately 30 mum). To test the accuracy, flexibility and utility of our system, we performed optogenetic analyses of the worm motor circuit, egg-laying circuit and mechanosensory circuits that have not been possible with previous methods.

DOI of Published Version



Nat Methods. 2011 Feb;8(2):147-52. Epub 2011 Jan 16. Link to article on publisher's site

Journal/Book/Conference Title

Nature methods

Related Resources

Link to Article in PubMed

PubMed ID