USA scientists transfer memory from one snail to another by transplanting RNA

Tuesday, 15 May, 2018

"If circulating neural RNAs can transfer behavioral states and tendencies, orchestrating both the transient feeling and the more permanent memory, it suggests that human memory-just like mood-will only be explained by exploring the interplay between bodies and brains".

UCLA biologists report they have transferred a memory from one marine snail to another, creating an artificial memory, by injecting RNA from one to another. He found the recipient sea snails became sensitised, suggesting the "memory" of the electrical shocks had been transplanted. The team's research is published May 14 in eNeuro, the online journal of the Society for Neuroscience.

Next, the team took some ribonucleic acid (RNA), which forms proteins based on cells' DNA, from nerve tissue in the upper abdomen of trained snails and injected it into the untrained snails' necks to get to their circulatory system. After these shocks were administered. the snail's defensive withdrawal reflex - where the snails contract in order to protect themselves from harm. When the researchers subsequently tapped the snails, they found those that had been given the shocks displayed a defensive contraction that lasted an average of 50 seconds, a simple type of learning known as "sensitization". That makes the animals more sensitive, so that in response to stimuli they defensively withdraw for longer than they normally would.

Scientists extracted RNA from the nervous systems of the snails that received the shocks and injected it into a small number of marine snails that had not been sensitised in this way.

They saw a similar effect when they did the same thing to sensory nerve cells being studied in petri dishes.

"I think not long from now, we could possibly utilize RNA to enhance the impacts of Alzheimer's malady or post-awful pressure issue", said David Glanzman, senior creator of the investigation and a UCLA educator of integrative science and physiology and of neurobiology.

In an experiment to test the idea, Glanzman implanted wires into the tails of California sea hares, or Aplysia californica, and gave them a series of electric shocks. "So these snails are alarmed and release ink, but they aren't physically damaged by the shocks", he said. The experiment could eventually lead to new treatments for restoring memory in Alzheimer's patients or to reduce traumatic memories. In the 1940s, Canadian psychologist Donald Hebb proposed memories are made in the connections between neurons, called synapses, and stored as those connections grow stronger and more abundant. The paper might support hints from studies conducted decades ago that RNA was involved in memory. These are commonly used as animal models for neuroscience because the cellular and molecular processes at work are relatively similar to humans, but they have a far more manageable number of neurons - about 20,000, compared to our 100 billion.