Protein Transport in Neurons

Evidence supports the synthesis of some axonal proteins at the level of the axon, which has provided a plausible mechanism for an integration of the metabolism of the neuron and has broadened the understanding of the role of the neurons.

Abstract

This chapter provides the evidence supporting the concept of axonal transport and focuses on the involvement of axonal transport in the control and integration of neuronal metabolism. The mechanism of axonal transport is selective and certain neuronal components, such as ribosomes do not appear to be transported from the soma into the axon. Axonal proteins, which are synthesized in the soma and transported somatofugally into the axon appear to consist at least two primary components: (a) a fast component with a velocity of 100–500 mm/day and (b) a slow component with a velocity of 0.4–3.0 mm/ day. Although the neuron soma is the primary source of axonal protein synthesis, evidence supports the synthesis of some axonal proteins at the level of the axon. Axonal transport has provided a plausible mechanism for an integration of the metabolism of the neuron, and the concept of molecular transport within the axon has broadened the understanding of the role of the neuron.