ABSTRACT
Although translation of cytosolic proteins is well described inaxons, much less is known about the synthesis, processing andtrafficking of transmembrane and secreted proteins Acanonical rough endoplasmic reticulum or a stacked Golgiapparatus has not been detected in axons, generating doubtsabout the functionality of a local route However, axons containmRNAs for membrane and secreted proteins, translationfactors, ribosomal components, smooth endoplasmicreticulum and post-endoplasmic reticulum elements that maycontribute to local biosynthesis and plasma membranedeliveryHere we consider the evidence supporting a localsecretory system in axons We discuss exocytic elementsand examples of autonomous axonal trafficking that impactdevelopment and maintenance We also examine whetherunconventional post-endoplasmic reticulum pathways mayreplace the canonical Golgi apparatus