Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

LCD Projector Used to Control Brain & Muscles of Tiny Organisms

17.01.2011
Researchers are using inexpensive components from ordinary liquid crystal display (LCD) projectors to control the brain and muscles of tiny organisms, including freely moving worms. Red, green and blue lights from a projector activate light-sensitive microbial proteins that are genetically engineered into the worms, allowing the researchers to switch neurons on and off like light bulbs and turn muscles on and off like engines.

Use of the LCD technology to control small animals advances the field of optogenetics -- a mix of optical and genetic techniques that has given researchers unparalleled control over brain circuits in laboratory animals. Until now, the technique could be used only with larger animals by placement of an optical fiber into an animal’s brain, or required illumination of an animal’s entire body.

A paper published Jan. 9 in the advance online edition of the journal Nature Methods describes how the inexpensive illumination technology allows researchers to stimulate and silence specific neurons and muscles of freely moving worms, while precisely controlling the location, duration, frequency and intensity of the light.

“This illumination instrument significantly enhances our ability to control, alter, observe and investigate how neurons, muscles and circuits ultimately produce behavior in animals,” said Hang Lu, an associate professor in the School of Chemical & Biomolecular Engineering at the Georgia Institute of Technology.

Lu and graduate students Jeffrey Stirman and Matthew Crane developed the tool with support from the National Institutes of Health and the Alfred P. Sloan Foundation.

The illumination system includes a modified off-the-shelf LCD projector, which is used to cast a multi-color pattern of light onto an animal. The independent red, green and blue channels allow researchers to activate excitable cells sensitive to specific colors, while simultaneously silencing others.

“Because the central component of the illumination system is a commercially available projector, the system’s cost and complexity are dramatically reduced, which we hope will enable wider adoption of this tool by the research community,” explained Lu.

By connecting the illumination system to a microscope and combining it with video tracking, the researchers are able to track and record the behavior of freely moving animals, while maintaining the lighting in the intended anatomical position. When the animal moves, changes to the light’s location, intensity and color can be updated in less than 40 milliseconds.

Once Lu and her team built the prototype system, they used it to explore the “touch” circuit of the worm Caenorhabditis elegans by exciting and inhibiting its mechano-sensory and locomotion neurons. Alexander Gottschalk, a professor in the Johann Wolfgang Goethe-University Frankfurt Institute of Biochemistry in Frankfurt, Germany, and his team provided the light-sensitive optogenetic reagents for the Georgia Tech experiments.

For their first experiment, the researchers illuminated the head of a worm at regular intervals while the animal moved forward. This produced a coiling effect in the head and caused the worm to crawl in a triangular pattern. In another experiment, the team scanned light along the bodies of worms from head to tail, which resulted in backward movement when neurons near the head were stimulated and forward movement when neurons near the tail were stimulated.

Additional experiments showed that the intensity of the light affected a worm’s behavior and that several optogenetic reagents excited at different wavelengths could be combined in one experiment to understand circuit functions. The researchers were able to examine a large number of animals under a variety of conditions, demonstrating that the technique’s results were both robust and repeatable.

“This instrument allowed us to control defined events in defined locations at defined times in an intact biological system, allowing us to dissect animal functional circuits with greater precision and nuance,” added Lu.

While these proof-of-concept studies investigated the response of C. elegans to mechanical stimulation, the illumination system can also be used to evaluate responses to chemical, thermal and visual stimuli. Researchers can also use it to study a variety of neurons and muscles in other small animals, such as the zebrafish and fruit fly larvae.

“Experiments with this illumination system yield quantitative behavior data that cannot be obtained by manual touch assays, laser cell ablation, or genetic manipulation of neurotransmitters,” said Lu.

Abby Robinson | Newswise Science News
Further information:
http://www.gatech.edu

More articles from Health and Medicine:

nachricht Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University

nachricht The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

Construction of practical quantum computers radically simplified

05.12.2016 | Information Technology

NASA's AIM observes early noctilucent ice clouds over Antarctica

05.12.2016 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>