Neuronal growth investigated by traction force and atomic force microscopy

During brain development, neurons actively grow axons that steer over distances ranging from tens to hundreds of cell diameters in length to locate target dendrites from other neurons and form neuronal networks. Axonal growth is largely controlled by a complex interplay between intrinsic and extrinsic factors, including genetic programming, biochemical signaling, cytoskeletal dynamics, and extracellular cues. Here I will present experimental results obtained by measuring traction forces and stresses exerted by neurons on the growth substrate during axonal extension. We also investigate how the traction forces and the elastic modulus of neurons change upon disruption of cell adhesion and of the actin intracellular dynamics . Our results highlight the interplay between neuron biomechanical properties, internal cytoskeletal dynamics, and external cues in generating traction forces, and open up new directions for future investigations of axonal growth and the formation of neuronal networks.