During development, neurons extend axons throughout the nervous system, establishing connections with postsynaptic targets that are often located long distances away from their somata. The ability of these young neurons to robustly extend their axons is dramatically diminished in adulthood, and this reduced intrinsic growth capacity is a key mechanism underlying the inability of adult central nervous system (CNS) neurons to regenerate their axons following injury.
We focus primarily on the corticospinal (CST) system because it is the most important voluntary motor projection in humans and is especially refractory to regeneration attempts. Taking a large data approach to CST regeneration through RNA sequencing and proteomic efforts, our aim is to identify regeneration specific mechanisms that contribute to CST axon growth and augment these pathways and mechanisms in the adult CST following spinal cord injury.
Similarly, the corticospinal system contributes to fine motor control that is absent at birth in most mammals but gradually emerges during subsequent maturation of CST circuitry. The nature of circuit development and reorganization during this period remains largely unexplored. Utilizing RNA sequencing techniques we begin to identify the learning transcriptome of the CST to better understand what facilitates CST control of movement and what promotes sustained synaptic circuitry.
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[This paper was featured in Nature Reviews Neuroscience 81: 656 (2007)].
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[This paper was featured in Journal of Cell Biology 178:965-80]
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