Microtubules are a major component of the cytoskeleton of nerve cells and are necessary for the formation and maintenance of neuronal structure. In order to provide material for neuronal growth and to preserve neuronal structure, microtubule proteins, along with other cytoskeletal proteins, are transported at a slow rate down neuronal extensions. The PI has discovered that microtubule preparations can undergo slow, energy-dependent, contractile behavior in vitro and has proposed that this process, microtubule gelation-contraction, is related to the normal process of protein transport in nerve cells. The proposed experiments will help demonstrate the validity of this hypothesis. Experiments will be performed to directly compare the properties of neuronal transport in vivo to microtubule gelation-contraction in vitro. The PI will attempt to identify the enzyme needed for the conversion of chemical energy into kinetic energy in this process. The experiments should provide important information on how nerve cell structure is produced and maintained and could have significance in understanding the processes leading to neuronal degeneration such as occurs in Alzheimer's disease and diabetic neuropathy.
