Mitochondria - A Potential Roadblock for Axonal Transport

Axonal transport of materials in neurons is an important process that directly affects the survival of neurons. Moreover, defects in this process have been linked to various neurodegenerative diseases. This work examines the interaction between mitochondria and cargoes transported along axon of dorsal root ganglion neurons using two-color imaging on a pseudo-TIRF setup. The result shows that cargoes transported along axon are more likely to slow down and pause in the vicinity of mitochondria. This propensity increases when drug is used to induce mitochondrial swelling. This can be explained as the large size of mitochondria (relative to the thin shaft of axon) can potentially inhibit cargo transport in axon through steric hindrance. Moreover, this finding also indicates that swollen mitochondria observed in some neurogenerative diseases may be one of the causes for axonal transport failure.