New research on a protein found in mosquitos may have increased our understanding of brain communication pathways, which may help scientists develop new therapies to treat neurological and psychiatric conditions.
Using a light-sensitive protein derived from mosquitos, Prof. Ofer Yizhar and his team in the Weizmann Institute of Science’s Neurobiology Department created a new method for discovering messages that are passed neuron to neuron in the brain of mice. Referring to the technique as "reverse engineering," Yizhar and his team developed optogenetic methods to understand better brain circuit function.
Proteins called rhodopsins via optogenetics can control the activity of neurons in mice, which allowed Yitzhar to influence the behavior of certain neurons when he and his team shined a beam of light into the his lab mouse's brain.
“We can detect the presence of the various neurotransmitters, but different neurons ‘read’ those neurotransmitters differently,” he says. “Optogenetics enables us to not only see the ‘ink,’ but really to decipher the ‘message’,” Yitzhar noted.
The goal of the research is to ultimately create a better version of rhodopsins than those currently available,
Multiple variations of the rhodopsin molecule can be found in nature, including in fish, insects and mammals, which may have an impact of circadian cycles. Using a mosquito rhodopsin molecule, the researchers found that neurons that produce the mosquito sensor are affected by the light, leading to an impact on the brain's synapses that can be controlled in space and time.
The researchers were able to illuminate the hemisphere expressing the mosquito rhodopsin with green light, prompting a one-sided bias in the mice's behavior.
“One of the major advantages of the mosquito rhodopsin is that it’s biostable – that is, it does not need refreshing – and it is potentially very specific, so that we can control just the precise synapses in which we are interested,” says Yizhar.
“This is a very exciting technology, since it will allow us to discover the roles of specific pathways in the brain in a way that was not possible before. We think this mosquito protein could open the way to developing a whole family of new optogenetic tools for use in neuroscience research,” he added.