RNA, or ribonucleic acid, has been widely known as a cellular messenger that makes proteins and carries out DNA's instructions to other parts of the cell.
The work of Glanzman and his team, however, lends weight to an emerging counter-theory that suggests long-term memory is actually stored within the cell bodies of the neurons themselves.
The RNA in the trained snail was used to create an engram - the elusive substrate of memory - by sensitising them with tail simulation that triggers an involuntary defensive reflex.
Some of the new snails received RNA from the trained cohort, and some, as controls, from the untrained group. When tapping the snails, the ones in shock training contracted their bodies for nearly 50 seconds to defend themselves. When these snails were prodded gently, they withdrew their siphons and gills-a reflexive defense response-for around 50 seconds.
Even though they had not received any shocks, the snails injected with the RNA acted as though they were the ones to have been shocked, contracting for about 40 seconds.More news: Voters must select party or nonpartisan ballot
"So, these snails are alarmed and release ink, but they aren't physically damaged by the shocks", he explained. After the shocks, scientists took RNA from the slugs that were shocked and injected it into slugs that hadn't been shocked. They bathed the untrained neurons in RNA from trained cells, then gave them a shock, and saw that they fired in the same way that trained neurons do.
The world's first memory transplant was just achieved in marine snails.
"If memories were stored at synapses, there is no way our experiment would have worked", said Glanzman, who added that the marine snail is an excellent model for studying the brain and memory. He said that if the memories were held in the synapses that the experiment would not have been able to work.
When asked if this process would be conducive to the transplant of memories laid down through life experiences, Prof Glanzman was uncertain, but he expressed optimism that the greater understanding of memory storage would lead to a greater opportunity to explore different aspects of memory. Scientists believe that in the future their method can be a tool to restore the memory of people with Alzheimer's disease.
Unlike these setups, which tend to look at how the neuron networks themselves are involved in memory, Glanzman's group is using RNA to tinker with memory. He and his colleagues published research in the journal eLife in 2014 indicating that lost memories can be restored.
The research was funded by the National Institute of Neurological Disorders and Stroke, the National Institute of Mental Health and the National Science Foundation.