Abstract

Neuronal growth is essential for nervous system development and is also required for regeneration after nervous tissue injury. Recent in vitro studies suggest that neuronal growth can also be regulated by mechanical properties of the substrate; however, the role of mechanical cues in axon pathfinding in vivo, and the spatiotemporal dynamics of tissue mechanics during early nervous system development, are still largely unknown. I am investigating the role of tissue stiffness in axon guidance within the early embryo, using the Xenopus laevis optic tract as a model system. I find that the path of optic tract growth is correlated with stiffness gradients in the living brain, before growth stalls after reaching the softer region. This is consistent with a role for substrate mechanics in axon pathfinding.