Even a simple action, such as the twitching of a mouse’s whisker, requires the coordinated activity of thousands of neurons that relay information from the brain to the muscles and back again. Eric Schreiter is creating tools to help scientists visualize and dissect these informational pathways, allowing researchers to gain a better understanding of neuronal circuits and their roles in complex behaviors.
One of the tools Schreiter and his colleagues developed is a genetically encoded molecule that permanently marks neurons as they fire. The molecule – a fluorescent protein called CaMPARI – changes from green to red when calcium floods a nerve cell that is activated at a specific time. Because this mark is permanent, it frees scientists from the need to focus a microscope on the right cells at just the right time to observe neuronal activity.
Now, Schreiter’s lab group is working on tools related to CaMPARI to both mark and manipulate active neurons at any specific time. His team is also developing new types of genetically encoded voltage indicators to visualize the electrical signaling that occurs in active neurons.