New Optogenetic Tool Can Be Used to Manipulate Neuronal Signaling

A team of scientists from the National Institute of Physiological Sciences in Japan has discovered that CaMKII activation is sufficient for long-term potentiation of individual dendritic spines. Their findings were published in Nature Communications. 

The team fused CaMKII with a specific domain of a plant photoreceptor. This domain—called LOV2-Jα—caused CaMKII to become sensitive to light, after which they expressed this new photoactivatable CaMKII in different types of isolated neurons and in living mice. 

"We were very excited to find that activating CaMKII triggers some important effects, specifically recruiting receptors that cause a chain reaction that then leads to long-term potentiation," lead researcher Hideji Murakoshi explains. The process physically changes the dendritic spines, expanding them, an outcome that the scientists also observed in their experiments. 

The team also used light-based imaging technology and the light-activated CaMKII to determine what signaling molecules are activated during long-term potentiation. All of these findings combine to provide a better picture of how long-term potentiation occurs at the synapse level. "In addition to the valuable information we uncovered about an important neurological process, our light-activated CaMKII is a major addition to existing optogenetic tools," Murakoshi comments when asked about the significance of their work. "We've created something that can be used to manipulate neuronal signaling and investigate synaptic plasticity—or the physiological changes that happen at individual synapses during events like memory formation."