Jessell received the award for his research on the embryonic development of the nervous system. His primary interest is the development of the spinal cord, which because of its relative simplicity and evolutionary conservation offers an ideal system for understanding general principles of central nervous system development.
Jessell’s work has revealed the molecular mechanisms responsible for establishing the spatial organization of the spinal cord. He has identified diffusible signaling molecules that act during early development to provide "positional information" to embryonic cells, instructing them to differentiate in ways that are appropriate for their specific locations within the cord. Jessell has also studied the molecular mechanisms by which developing cells respond to these positional cues. This work has led to the identification of a transcriptional code, whereby a set of regulatory genes act in combination to specify the many different cell types that comprise the mature spinal cord.
The discovery of these genetic mechanisms has made it possible to identify and manipulate the activity of specific classes of neurons with great precision, and Jessell has used this approach to reveal the link between functional circuitry and motor behavior.
In addition to fundamental questions, Jessell’s work has important practical implications for the emerging field of regenerative medicine. There is great interest in stem cells as a renewable source of cells for transplantation therapy and drug discovery, but for this approach to succeed, stem cells must be converted to the desired cell type. Jessell’s work on transcriptional control of neural identity provides a roadmap for such efforts, and he has demonstrated its feasibility by converting embryonic stem cells into spinal motor neurons, the same cell types that degenerate in diseases such as amyotrophic lateral sclerosis. The implications of his research go well beyond motor neuron diseases; many disorders of the nervous system affect particular cell types, and the ability to convert stem cells to specific classes of neurons may eventually find wide applications in clinical neuroscience.
The McGovern Institute will award the Scolnick Prize to Dr. Jessell on Monday, April 1, 2013. He will deliver a lecture entitled “Sifting Circuits for Motor Control" at 4 p.m. that day, to be followed by a reception, at the McGovern Institute in the Brain and Cognitive Sciences Complex, 43 Vassar Street (building 46, room 3002). The event is free and open to the public.