A Tohoku University research group led by Dr. Hiromu Yawo, Professor of Graduate School of Life Sciences and a PI of the MEXT-SRPBS, elucidated the structure-function relationship of channelrhodopsins (ChRs).  Based on this relationship, they designed a novel channelrhodopsin variant, channelrhodopsin green receiver （ChRGR） with marked improvements in photosensitivity to green light, temporal accuracy and resolution.  They also genetically engineered the motor cortical neurons of mice to express ChRGR, and focused the sinusoidal wave of green LED light on the brain with variable frequency.  They found that the neuronal firings were tuned at 3 to 10 Hz in the cortical network.  It appears that the wave of green LED triggers the cortical network to transit from the silent state under anesthesia to more active state with outputs to the spinal motor centers.  A combination of ChRGR and optically generated patterned activity is expected to make a powerful system to directly drive a brain (Opto-current-clamp method).  The above work will be published online soon in Public Library of Science (PLoS) ONE, a highly praised journal of biology and medicine, under a title “Opto-current-clamp Actuation of Cortical Neurons using a Strategically Designed Channelrhodopsin.”

More Information (Japanese)

[Contact]
Professor Hiromu Yawo, MD. PhD.
Tohoku University Graduate School of Life Sciences
TEL: +81-22-217-6208
E-mail: yawo-hiromu*m.tohoku.ac.jp (Replace * with @)

(Public Relations)
Associate Professor Fuji Nagami
Tohoku Neuroscience Global COE
TEL: +81-22-717-7908, FAX: +81-22-717-7923
E-mail: f-nagami*med.tohoku.ac.jp (Replace * with @)