Structural and Molecular Aspects of Axonal Function in Large Mammals

Classical nerve cells harbor diverse processes, which are need for efficient long distance communication of the nervous system. In contrast to short and ramified dendrites, axons do not branch much and extend for long distances. Axons transform chemical energy to mechanical movement of molecular motors to provide timely delivery of axonal cargoes to their final destinations ranging from the presynaptic area, axonal shaft compartments and cell bodies. Interestingly, axons have adapted during the evolution of different kind of animals. In example, in big animals such as whales and giraffes axons span from app. 32 to 8 meters, in humans for app. 1 meter length and in mice for a couple of millimeters. This raises the question of how does axonal transport differ when axonal cargoes need to be transported for dozen of meters versus millimeters? We posit that long-distance axonal transport developed efficient ways to deal with length and energy demands, which remain currently unexplored.