WOODS HOLE, Mass. -- For the first time, researchers have identified a peptide that can spur cargo transport in nerve cells, a discovery that could help scientists better understand nerve cell function and test possible therapies for neurodegenerative diseases.
Elaine Bearer, a professor at Brown Medical School, led the research, which was conducted at the MBL (Marine Biological Laboratory) in Woods Hole, Mass., where Bearer was a Dart Scholar and is a Whitman investigator. Published in the Proceedings of the National Academy of Sciences online early edition, the research shows that a peptide, or protein bit, can hitch biological material onto molecular motor machinery, acting as a "ZIP Code" that directs the shipment to the synapse.
The peptide comes from amyloid precursor protein, or APP, a principal component of plaques found in the brains of people with Alzheimer's disease. Scientists have long known that APP can break down and form these plaques and that mutations in this protein lead to early onset of Alzheimer's disease. Until now, however, little was understood about the function of APP in healthy nerve cells.
The research also sheds light on the complex intracellular transport system inside nerve cells. This transport system is critical to nervous system function, bringing proteins and RNA from the cell body down a neuron's spindly axon to the synapse, the major site of information exchange and storage in the nervous system. Without this precious cargo, neurons can't communicate. Memories can't be made. Learning can't take place. And neurons die.
"This neuronal transport system is incredibly important, but until now, we didn't know what actually attaches the cargo to the motor and gives it a 'ZIP Code' or address to ship it to. Our work shows that the cargo-motor hitch is as simple as a short peptide," Bearer said. "We've identified the first of these molecular dispatchers a short peptide from the Alzheimer's prot
Contact: Wendy Lawton