"The main issue that challenges neuroscientists’ understanding of memory is that proteins don’t last very long in the brain, even though memories last nearly a lifetime. So for memories to remain, there must be plastic changes, meaning that neuron structures actually have to change as a result of memory consolidation.
This is where Arc comes into play. Previous research on rats illustrated how Arc disrupts memory consolidation, suggesting that Arc is vital in neuronal plasticity.
But scientists never thought they would stumble on evidence that pointed to a viral origin for Arc, as these findings suggest.
The research team needed to verify this theory, so they tested whether Arc actually acts like a virus. It turns out the Arc capsid encapsulated its own RNA. When they put the Arc capsids into a mouse brain cell culture, the capsids transferred their RNA to the mouse brain cells — just like viral infection does.
“We went into this line of research knowing that Arc was special in many ways, but when we discovered that Arc was able to mediate cell-to-cell transport of RNA, we were floored,” says the study’s lead author, ....“No other non-viral protein that we know of acts in this way.”
The researchers suspect this virus-mammal collaboration happened sometime between