Patterns of spinal sensory-motor connectivity prescribed by a dorsoventral positional template.
Sensory-motor circuits in the spinal cord are constructed with a fine specificity that coordinates motor behavior, but the mechanisms that direct sensory connections with their motor neuron partners remain unclear. The dorsoventral settling position of motor pools in the spinal cord is known to match the distal-to-proximal position of their muscle targets in the limb, but the significance of invariant motor neuron positioning is unknown. An analysis of sensory-motor connectivity patterns in FoxP1 mutant mice, where motor neuron position has been scrambled, shows that the final pattern of sensory-motor connections is initiated by the projection of sensory axons to discrete dorsoventral domains of the spinal cord without regard for motor neuron subtype or, indeed, the presence of motor neurons. By implication, the clustering and dorsoventral settling position of motor neuron pools serve as a determinant of the pattern of sensory input specificity and thus motor coordination.
Kavli Institute for Brain Science, Department of Neuroscience, Columbia University, New York, NY 10032, USA.
Gülşen
G
Sürmeli
Turgay
T
Akay
Gregory C
GC
Ippolito
Philip W
PW
Tucker
Thomas M
TM
Jessell
D000818:Animals; D019521:Body Patterning; D004576:Electromyography; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D006614:Hindlimb / Q000294:innervation; D051379:Mice; D009046:Motor Neurons / Q000378:metabolism*; D009154:Mutation; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D011984:Sensory Receptor Cells / Q000378:metabolism; D013116:Spinal Cord / Q000196:embryology* / Q000378:metabolism*
D051858:Forkhead Transcription Factors; C432917:Foxp1 protein, mouse; D012097:Repressor Proteins