Navigation Links
Sharply focused on neurons, light controls a worm's behavior

CAMBRIDGE, Mass., Jan. 18, 2011 -- Physicists and bioengineers have developed an optical instrument allowing them to control the behavior of a worm just by shining a tightly focused beam of light at individual neurons inside the organism.

The pioneering optogenetic research, by a team at Harvard University, the University of Pennsylvania, and the University of Massachusetts Medical School, is described this week in the journal Nature Methods. Their device is known as the CoLBeRT (Controlling Locomotion and Behavior in Real Time) system for optical control of freely moving animals, in this case the millimeter-long worm Caenorhabditis elegans.

"This optical instrument allows us to commandeer the nervous system of swimming or crawling nematodes using pulses of blue and green light -- no wires, no electrodes," says Aravinthan D.T. Samuel, a professor of physics and affiliate of Harvard's Center for Brain Science. "We can activate or inactivate individual neurons or muscle cells, essentially turning the worm into a virtual biorobot."

Samuel and colleagues chose to work with C. elegans, an organism often used in biological research, because of its optical transparency, its well-defined nervous system of exactly 302 neurons, and its ease of manipulation. They genetically modified the worms so their neurons express the light-activated proteins channelrhodopsin-2 and halorhodopsin.

In conjunction with high-precision micromirrors that can direct laser light to individual cells, the scientists were then able to stimulate -- using blue light -- or inhibit -- using green light -- behaviors such as locomotion and egg-laying.

"If you shine blue light at a particular neuron near the front end of the worm, it perceives that as being touched and will back away," says co-author Andrew M. Leifer, a Ph.D. student in Harvard's Department of Physics and Center for Brain Science. "Similarly, blue light shined at the tail end of the modified worm will prompt it to move forward."

The scientists were also able to use pulses of light to steer the worms left or right. By stimulating neurons associated with the worm's reproductive system, they were even able to rouse the animal into secreting an egg.

Key to the CoLBeRT system is a tracking microscope recording the motion of a swimming or crawling worm, paired with image processing software that can quickly estimate the location of individual neurons and instruct a digital micromirror device to illuminate targeted cells. Because cells in an unrestrained worm represent a rapidly moving target, the system can capture 50 frames per second and attain spatial resolution of just 30 microns.

"This development should have profound consequences in systems neuroscience as a new tool to probe nervous system activity and behavior, as well as in bioengineering and biorobotics," Samuel says. "Our laboratory has been pioneering new optical methods to study the nervous system, and this is the latest, and perhaps our greatest, invention."


Contact: Steve Bradt
Harvard University

Related biology news :

1. Measurements of CO2 and CO in Chinas air indicate sharply improved combustion efficiency
2. Proposed dietary guidelines for Americans sharply debated
3. 7 CAMH scientists win Young Investigator awards focused on breakthrough research
4. NIH renews Nanomedicine Center focused on treating single-gene disorders for $16.1 million
5. NIH expands network focused on how genes affect drug responses
6. For ever and ever: When the wedding flight never ends
7. Ammonites last meal: New light on past marine food chains
8. New book highlights the cellular and molecular determinants of brain wiring
9. UNC scientists pinpoint link between light signal and circadian rhythms
10. Scripps scientists see the light in bizarre bioluminescent snail
11. Unlocking the secrets of a plants light sensitivity
Post Your Comments:
(Date:11/20/2015)... , November 20, 2015 ... company focused on the growing mobile commerce market and ... Gino Pereira , was recently interviewed on ... will air on this weekend on Bloomberg Europe ... America . --> NXTD ) ("NXT-ID" or ...
(Date:11/18/2015)... --> --> ... report titled  Gesture Recognition Market - Global Industry Analysis, ... to the report, the global gesture recognition market was valued at ... US$29.1 bn by 2021, at a CAGR of 20.3% ... dominated the global gesture recognition market in ...
(Date:11/17/2015)... 17, 2015 Pressure BioSciences, Inc. (OTCQB: PBIO) ... and sale of broadly enabling, pressure cycling technology ("PCT")-based ... today announced it has received gross proceeds of $745,000 ... Placement (the "Offering"), increasing the total amount raised to ... additional closings are expected in the near future. ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... November 26, 2015 ... Market 2016 - 2020 report analyzes that automating ... and quality in long-term samples, minimizing manual errors, ... Automation minimizes manual errors such as mislabeling or ... Further, it plays a vital role in blood ...
(Date:11/25/2015)... HOLLISTON, Mass. , Nov. 25, 2015 ... HART ), a biotechnology company developing bioengineered organ implants ... McGorry will present at the LD Micro "Main ... 2:30 p.m. PT. The presentation will be webcast live ... Management will also be available at the conference for ...
(Date:11/25/2015)... 25, 2015 Orexigen® Therapeutics, Inc. (Nasdaq: ... a fireside chat discussion at the Piper Jaffray 27th ... . The discussion is scheduled for Wednesday, December 2, ... .  A replay will be available for 14 days ... , Julie NormartVP, Corporate Communications and Business Development , ...
(Date:11/24/2015)... ... , ... The United States Golf Association (USGA) today announced Dr. Bruce Clarke, ... annually since 1961, the USGA Green Section Award recognizes an individual’s distinguished service to ... Clarke, of Iselin, N.J., is an extension specialist of turfgrass pathology in the department ...
Breaking Biology Technology: