Neurons (nerve cells) in the brain and central nervous system relay messages to each other by releasing neurotransmitters. For the message to be received, neurotransmitter receptors and associated proteins must be strategically transported to the synapse, the site of contact between neurons. Defects in the transportation of proteins is thought to affect neuronal activity and ultimately may lead to neurological impairments like epilepsy and mental retardation. Marie-France Lise is studying this fundamental process – how the molecules important for normal brain functions are transported throughout the neurons from their site of synthesis to their specific site of action. Her research focuses on a family of neuronal proteins known as Myosin V, thought to be important regulators of protein transport. These proteins act as molecular motors by binding and “walking” cargoes along actin filament highways, leading to different destinations within the cell. By characterizing how the Myosin V family regulates transport of proteins in neurons, Marie-France hopes to gain a better understanding of how synapses are formed during brain development, learning, and memory formation.