Axon and dendritic trafficking.

Neuronal trafficking is crucial to the formation and dynamics of presynaptic and postsynaptic structures and the development and maintenance of axonal and dendritic processes. The mechanism for delivering specific organelles and synaptic molecules in axons and dendrites primarily depends on molecular motor proteins that move along the cytoskeleton. Adaptor proteins, regulatory molecules and local signaling pathways provide additional layers of specificity and control over bidirectional movement, polarized transport and cargo delivery. Here we review recent advances and emerging concepts related to the transport machinery of crucial neuronal components, such as mitochondria and presynaptic cargoes, and the mechanisms that modulate their polarized axo-dendritic sorting and synaptic delivery.