434: An Off-and-On Switch for Controlling Animals?

The New York Times > Science > An Off-and-On Switch for Controlling Animals?:

[R]esearchers at Yale have done Galvani one better. They can make fruit flies walk, leap or fly by shining a laser at the insects, setting off certain neurons inside them.

It's possible, at least in theory, that this method could someday be developed into a sort of animal remote control. But its biggest promise is as a scientific tool that may shed light on the function of different kinds of neurons. The ability to switch on particular neurons may allow scientists to discover clues about a range of disorders, from Parkinson's disease to drug addiction.

Dr. Susana Lima and Dr. Gero Miesenböck, the authors of the study, engineered a light-sensitive trigger that could be attached to neurons of flies.

The researchers began their work by transplanting a gene related to the structure of certain pain-sensing neurons in rats. Dr. Lima and Dr. Miesenböck added genetic on-switches to the rat gene so that it would become active only in a particular type of neuron in a fly.

To turn the transplanted rat channels into light-sensitive triggers, Dr. Lima and Dr. Miesenböck then took advantage of the way the altered neurons produced electric impulses. Unlike fly neurons, the altered cells could produce electric impulses only in the presence of a molecule called ATP.

Very cool. Using the shared architecture of rats and flies, shared because of common descent, they are learning to control fly neurons. By controlling that, they hope to have similar control over vertebrate neurons, curing diseases like Parkinson's.