The vertebrate spinal cord contains a central pattern generator (CPG) capable of producing coordinated locomotion (e.g., walking, swimming, flying), even in isolation from the brain. However, the neuronal populations that generate the locomotor rhythm are unknown. Identifying the neural populations that generate locomotion would remove a major barrier in the study of the modulation, degeneration and regeneration of locomotion. The objective of this application is to characterize one promising population of spinal neurons: the V3 interneurons. The V3 neurons satisfy two important criteria for locomotor rhythm generation: first, they are located in the ventral medial spinal cord and, second, they are glutamatergic. We hypothesize that V3 neurons are core components of the locomotor CPG. In order to test this hypothesis, we propose three aims. First, we will determine the activity and recruitment patterns of V3 neurons during fictive locomotion. Next, we will determine if V3 neurons have locomotion generating membrane properties. Finally, we will determine if the V3 neurons are necessary for normal locomotion. The completion of these three aims will give us a better understanding of the role of the v3 neurons in locomotion and the overall structure of the vertebrate CPG.

Public Health Relevance

Vertebrate locomotion is coordinated by neural circuits in the spinal cord called central pattern generators (CPGs). Spinal cord injury (SCI) can result in severe disruption of the spinal CPG, and repairing the spinal cord following SCI will require an understanding of the locomotor CPG. Our work will determine the role of a specific group of neurons called V3 interneurons in the CPG by measuring their necessity for locomotion, pattern of activity, and intrinsic membrane properties.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
1F31NS083110-01A1
Application #
8646239
Study Section
Special Emphasis Panel (ZRG1-F03B-A (20))
Program Officer
Chen, Daofen
Project Start
2013-09-09
Project End
2015-09-08
Budget Start
2013-09-09
Budget End
2014-09-08
Support Year
1
Fiscal Year
2013
Total Cost
$28,032
Indirect Cost
Name
University of Minnesota Twin Cities
Department
Neurosciences
Type
Schools of Medicine
DUNS #
555917996
City
Minneapolis
State
MN
Country
United States
Zip Code
55455
Wiggin, Timothy D; Peck, Jack H; Masino, Mark A (2014) Coordination of fictive motor activity in the larval zebrafish is generated by non-segmental mechanisms. PLoS One 9:e109117