Roads of growth: cytoskeleton-mediated mechanisms during neurodevelopment

Our brain contains billions of brain cells, neurons, that form networks to communicate information and is responsible for all bodily functions. To correctly perform these challenging tasks, neurons have a typical form. They consist of multiple components: they have a central cell body from which grow multiple heavily branched processes that can receive input from other cells, the dendrites. An axon also grows from the cell body; this is a relatively long and thin projection that can transmit information to other cells. To obtain and keep this particular form neurons have a cytoskeleton. Other than our own skeleton, the cytoskeleton is highly dynamic, and the organisation of the cytoskeleton is important for the growth of neurons. This thesis describes multiple studies that focus on changes in the cytoskeleton during neuronal development. Several types of cells are used: neurons inside a small, living worm (C. elegans), rat neurons that grow in a petri-dish, and human neurons derived from stem cells. Multiple processes that affect the organisation of the cytoskeleton during neurodevelopment have been identified. Some general mechanisms occur in the different species, but variations in developmental processes have also been found. This research increases our understanding of the development of young neurons and the growth of a healthy, well-functioning brain.