Drosophila cation channel protein as a novel thermogenetic tool to study neuronal function

Drosophila cation channel protein as a novel thermogenetic tool to study neuronal function

A team of neuroscientists are inching closer to developing the tools needed to decipher the brain. The team has published a new paper that demonstrates how proteins can be used as tools to regulate the activity of individual neurons in the brain through changes in temperature.

"Thermogenetic tools, which utilize heat to act as a 'switch' to turn neuron functions on, are expanding the horizons of brain research by allowing us to control specific neurons in the brain and measure behavioral changes," said the senior author. "The goal of this fundamental research was to identify more of these special proteins, laying the foundation so that, in the future, scientists have a better understanding of how neuronal circuits function."

The researchers focused on a family of genes that encode taste receptors found in fruit flies. Surprisingly, some of these taste receptors also are activated by heat and thus play a role in detecting environmental temperature.

First, the lab investigated the thermosensitivity of these proteins and identified one member of the family, called Gr28bD, as a prime candidate for thermogenetics. Then, using live-imaging techniques and software developed in their lab to demonstrate that the Gr28bD protein can, through temperature differences, modulate the brain activity of fruit flies.

Finally, the flies were tested in the lab for temperature-dependent behavior. Using a specially designed heat chamber that allows precise control of the environmental temperature, the researcehrs were able to show that the Gr28bD protein can control behavior in these flies, using temperature as a "brain switch."

"Gr28bD could become a powerful tool in controlling neuronal activity and studying how neuronal circuits function," said a graduate student. "Since this protein is not found in any mammal, it emerges as a good candidate for the development of novel thermogenetic tools to be used for basic research and potentially one day in humans."