The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.
This award will support a twenty-four-month research fellowship by Dr. Kimberly J. Dougherty to work with Dr. Ole Kiehn at Karolinska Institute in Stockholm, Sweden.
Neuronal networks in the central nervous system are responsible for all brain and spinal cord functions: memories, perception, movement, etc. Neuronal networks underlying rhythmic movements, such as walking, are located in the spinal cord. Many aspects of these rhythmic movements, including timing and coordination, are generated by these spinal networks called central pattern generators (CPGs). Until recently, part of the difficulty in identifying components of mammalian locomotor CPGs has been the large number of cells and lack of markers that reliably identify groups of neurons. Therefore, the use of genetic markers, such as transcription factors, provides a new exciting tool to classify CPG neurons. Chx10 is a transcription factor expressed in a population of spinal interneurons. Chx10 neurons are located in the intermediate region of the spinal cord (laminae VII-VIII), project ipsilaterally in both the ascending and descending directions, and are excitatory. Selective ablation of Chx10 neurons results in a motor phenotype in which left-right alternation is disrupted. This strongly suggests that these cells are interposed with commissural interneurons in CPG circuits and play an essential role in the mammalian CPG. The goal of this project is to determine the role of Chx10 cells in CPG circuitry. An understanding of the properties of Chx10 neurons, the activity of these neurons during locomotion, and the interconnections of these neurons will provide essential insight into the neural network responsible for locomotor behavior in mammals. A detailed understanding of normal spinal neuronal networks is also important to the recovery of locomotor loss following spinal cord injury. Additionally, neural networks are not unique to the spinal cord but are found throughout the central nervous system and are involved in virtually every aspect of central nervous system function. Dr. Kiehn's lab is one of the few labs in the world using a combination of molecular and electrophysiological approaches to study spinal cord CPGs. The Kiehn lab is on the cutting edge of spinal cord research, both in research questions and techniques used, and has pioneered recordings from identified populations of neurons in the intact rodent spinal cord.
