Cell migration plays a critical role during development, adult life, and in various diseases. Important examples include the growing tip of a nerve cell process, the neuronal growth cone, and the invasive behavior of cancer cells. Our laboratory investigates the underlying mechanisms of axonal growth, guidance, and regeneration. We use two main model systems, Aplysia and zebrafish. Using the large Aplysia neurons in culture, we investigate how growth cones integrate their sensor, signaling, and motility functions to achieve directional movements. The power of the zebrafish system enables us to study these processes in living organisms. Our current studies focus on reactive oxygen species (ROS) signaling and mechanosensing in neurite growth. A third project involves a drug screen using zebrafish larvae with the aim of identifying novel compounds that enhance axonal regeneration following spinal cord injury. We use a combination of quantitative live cell imaging, cell biological, biophysical, molecular and biochemical techniques to investigate the dynamics and function of adhesion, signaling, and cytoskeletal proteins, and to quantify forces involved in growth cone migration. We hope that our research will not only improve our understanding of the basic cell biology of neuronal growth cones, but also assist the development of new treatments that enhance axonal regeneration in nervous system diseases and injuries.