Prions and Memory

Prions Are Key to Preserving Long-Term Memories

The famed protein chain reaction that made mad cow disease a terror may be involved in helping to ensure that our recollections don't fade

Feb 18, 2014 |By Beth Skwarecki

A protein called Tob (green) binds and allows another protein, monomeric Orb2A (red) to persist intact in a neuron and thereby enable a chain reaction to maintain a permanent memory.
Credit: Nicolle Rager Fuller, Sayo-Art

Prions, the protein family notorious for causing "mad cow" and neurodegenerative diseases like Parkinson's, can play an important role in healthy cells. "Do you think God created prions just to kill?" mused Nobel laureate Eric Kandel. "These things must have evolved initially to have a physiological function." His work on memory helped reveal that animals make and use prions in their nervous systems as part of an essential function: stabilizing the synapses that constitute long-term memories. These natural prions aren't infectious but on a molecular level they chain up exactly the same way as their disease-causing brethren. (Some researchers call them "prionlike" to avoid confusion.) This week, work from neuroscientist Kausik Si of the Stowers Institute for Medical Research, one of Kandel's former students, shows that the prion's action is tightly controlled by the cell, and can be turned on when a new long-term memory needs to be formed./.../