Genetic Ablation of V2a Ipsilateral Interneurons Disrupts Left-Right Locomotor Coordination in Mammalian Spinal Cord

TY - JOUR

T1 - Genetic Ablation of V2a Ipsilateral Interneurons Disrupts Left-Right Locomotor Coordination in Mammalian Spinal Cord

AU - Crone, Steven A.

AU - Quinlan, Katharina A.

AU - Zagoraiou, Laskaro

AU - Droho, Steven

AU - Restrepo, Carlos Ernesto

AU - Lundfald, Line

AU - Endo, Toshiaki

AU - Setlak, Jennifer

AU - Jessell, Thomas M.

AU - Kiehn, Ole

AU - Sharma, Kamal

PY - 2008/10/9

Y1 - 2008/10/9

N2 - The initiation and coordination of activity in limb muscles are the main functions of neural circuits that control locomotion. Commissural neurons connect locomotor circuits on the two sides of the spinal cord, and represent the known neural substrate for left-right coordination. Here we demonstrate that a group of ipsilateral interneurons, V2a interneurons, plays an essential role in the control of left-right alternation. In the absence of V2a interneurons, the spinal cord fails to exhibit consistent left-right alternation. Locomotor burst activity shows increased variability, but flexor-extensor coordination is unaffected. Anatomical tracing studies reveal a direct excitatory input of V2a interneurons onto commissural interneurons, including a set of molecularly defined V0 neurons that drive left-right alternation. Our findings imply that the neural substrate for left-right coordination consists of at least two components; commissural neurons and a class of ipsilateral interneurons that activate commissural pathways.

AB - The initiation and coordination of activity in limb muscles are the main functions of neural circuits that control locomotion. Commissural neurons connect locomotor circuits on the two sides of the spinal cord, and represent the known neural substrate for left-right coordination. Here we demonstrate that a group of ipsilateral interneurons, V2a interneurons, plays an essential role in the control of left-right alternation. In the absence of V2a interneurons, the spinal cord fails to exhibit consistent left-right alternation. Locomotor burst activity shows increased variability, but flexor-extensor coordination is unaffected. Anatomical tracing studies reveal a direct excitatory input of V2a interneurons onto commissural interneurons, including a set of molecularly defined V0 neurons that drive left-right alternation. Our findings imply that the neural substrate for left-right coordination consists of at least two components; commissural neurons and a class of ipsilateral interneurons that activate commissural pathways.

KW - CELLBIO

KW - DEVBIO

KW - MOLNEURO

UR - http://www.scopus.com/inward/record.url?scp=53049089487&partnerID=8YFLogxK

U2 - 10.1016/j.neuron.2008.08.009

DO - 10.1016/j.neuron.2008.08.009

M3 - Journal article

C2 - 18940589

AN - SCOPUS:53049089487

SN - 0896-6273

VL - 60

SP - 70

EP - 83

JO - Neuron

JF - Neuron

IS - 1

ER -