A major puzzle for neurobiologists is how the brain can modify one microscopic connection, or synapse, at a time in a brain cell and not affect the thousands of other connections nearby. Plasticity, the ability of the brain to precisely rearrange the connections between its nerve cells, is the framework for learning and forming memories.
Duke University Medical Center researchers have identified a missing-link molecule that helps to explain the process of plasticity and could lead to targeted therapies.
The discovery of a molecule that moves new receptors to the synapse so that the neuron (nerve cell) can respond more strongly helps to explain several observations about plasticity, said Michael Ehlers, M.D., Ph.D., a Duke professor of neurobiology and senior author of the study published in the Oct. 31 issue of Cell. “This may be a general delivery system in the brain and in other types of cells, and could have significance for all cell signaling.”
Ehlers said this could be a general way for all cells to locally modify their membranes with receptors, a process critical for many activities — cell signaling, tumor formation and tissue development.
“Part of plasticity involves getting receptors to the synaptic connections of nerve cells,” Ehlers said. “The movement of neurotransmitter (chemical) receptors occurs through little packages that deliver molecules to the synapse when new memories form. What we have discovered is the molecular motor that moves these packages when synapses are active.”