Linkers, packages and pathways: new concepts in axonal transport

The molecular mechanisms that generate efficient and directed transport of proteins and organelles in axons remain poorly understood. In the past year , many studies have identified specific transmembrane or scaffold proteins that might link motor proteins to their cargoes, These studies have also id entified previously unsuspected pathways and raised the intriguing possibil ity that pre-packaged groups of functionally related proteins are transport ed together in the axon. Evidence suggests that fast molecular motor protei ns have a role in slow axonal transport, and the axonal transport machinery has been implicated in the genesis of neurodegenerative diseases.