Scientists Found a New Solution to Boom Long-lasting Memory—Molecular mTORC2
If we want to remember something for a long time, we need to through a procedure in which the long-term memory starts with a short-term memory and consolidation, such as repetition, as least that is what older studies showed. Several days ago, some researchers found another solution, a critical mechanism, a molecular—mTORC2 (mammalian target of rapamycin complex 2).
The research findings were published on the Nature Neuroscience.
Memories accompany us with our whole life. They record our happiness, sorrow, anger, excitement etc. But there are still some people that suffer memory-related conditions. Thus understanding the precise mechanism by which memories are stored in the brain will lead to the development of new treatments for conditions associated with memory loss.
From previous neuroscience studies, scientists have known that new protein synthesis derived from brain cells or brain neurons is decisive for memory storage. In the study, researchers found a new mechanism. They found mTORC2 regulates memory formation by modulating actin fibers, which is an important component of the architectural structure of the neuron. These actin fibers keep stable changes in synaptic strength.
In order to thoroughly figure out the mechanism, researchers used genetically-engineered mice, after turning off mTORC2 in the hippocampus and surrounding areas, they found these mice have normal short-term memory, but no long-term memories. Similar to human patients with injury in the hippocampus, these mutant mice were no longer able to form new long-lasting memories.
Humans and animals have evolved for a long time with millions of years, but the memory regulation role of mTORC2 on the mice suggested that its role has been maintained. Like mTORC2-deficient mice, fruit flies lacking TORC2 show defective long-term memory storage. So far, some researchers try to develop drugs targeting on the molecular as well as actin polymerization to facilitate the long-standing memory, for example, turning on mTORC2 or even actin polymerization.
The team has identified a small molecule that by activating mTORC2 and consequently actin polymerization enhances not only the synaptic strength between nerve cells but also long-term memory formation. In addition, researchers found that by directly promoting actin polymerization, with a second drug, long-term memory is generated more easily.