The molecules that are essential for normal brain functions are transported throughout neurons, travelling from the site of their formation to the specific location where they are activated. Defects in the transport and exchange of these molecules may affect brain activity and lead to neurological impairments such as epilepsy and mental retardation. Marie-France Lise is studying Myosin V, a family of proteins that may be important regulators of how molecules travel across neurons and reach their destinations. By characterizing how the Myosin V family regulates transport, she hopes to create a better understanding of how these processes contribute to essential brain development, learning and memory formation.