The development and maintenance of polarity is paramount to neuronal development and function. The loss of this cell state is realized in many neurodegenerative diseases and ultimately leads to cell death. This project will lead to a greater understanding of the mechanisms responsible for polarization and its maintenance. The goal of this project is to characterize the contribution that the recently discovered LKB1 kinase pathway plays in axon growth and branching through polarized transport of cargo.
Specific Aim 1 will provide the necessary framework for understanding how LKB1 and NUAK1/2 affect the transport of mitochondria in the axon.
Specific Aim 2 will characterize the mechanism by which transport is regulated by determining the downstream components of the kinase pathway. The interaction between LKB1/NUAK and the mitochondrial anchor protein syntaphilin will be the main focus of this aim.
Specific Aim 3 will then attempt to link mitochondrial transport in the axon to proper axon branching and projection within layer 2/3 neurons of the cortex. This research will provide important new knowledge that will be useful in understanding the basic mechanisms at work in many neurodegenerative diseases including Alzheimer's, Huntington's and Parkinson's.

Public Health Relevance

Neuron polarization is required for proper neuron function. Disruption of polarization and the mechanisms that underlie its maintenance are known to be major factors in many neurodegenerative diseases including ALS, Alzheimer's, Huntington's and Parkinson's.

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Postdoctoral Individual National Research Service Award (F32)
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Special Emphasis Panel (ZRG1-F03A-N (20))
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Riddle, Robert D
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Scripps Research Institute
La Jolla
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