Engineered Proteins Restore Light Sensitivity To Animals

The findings were presented at Neuroscience 2009, the annual meeting of the Society for Neuroscience and the world's largest source of emerging news about brain science and health.

In past studies, researchers made a blind animal's visual cells respond to light by introducing a light-sensitive algae protein into the eye. This new study manipulates existing proteins that our brains normally use to transmit information between neurons, and makes them light sensitive.

The researchers focused on several light-sensitive proteins, each with its own unique properties that could be fine- tuned to meet researchers' specific needs. One such engineered protein, LiGluR (Light Activated Glutamate Receptor), can turn neuronal activity on and off upon illumination with specific wavelengths of light. There are many glutamate receptors in the human brain, but they are not normally light sensitive.

"Our approach was to build on these initial studies, to 're-engineer nature,' by solving a deficit with engineered light-sensitive proteins," said Natalia Caporale, PhD, at the University of California Berkeley, the study's first author. "This approach could prove to be a viable therapeutic option for people who have lost significant vision and are in the late stages of retinal degeneration," she said.

Compared with naturally occurring photosensitive proteins, LiGluR can initiate larger and longer-lasting responses in neurons, making it a promising candidate for treatments intended to restore vision.

Research was supported by the Nanomedicine Development Center for the Optical Control of Biological Function and the Foundation Fighting Blindness.