V1 spinal neurons regulate the speed of vertebrate locomotor outputs.
The neuronal networks that generate vertebrate movements such as walking and swimming are embedded in the spinal cord. These networks, which are referred to as central pattern generators (CPGs), are ideal systems for determining how ensembles of neurons generate simple behavioural outputs. In spite of efforts to address the organization of the locomotor CPG in walking animals, little is known about the identity and function of the spinal interneuron cell types that contribute to these locomotor networks. Here we use four complementary genetic approaches to directly address the function of mouse V1 neurons, a class of local circuit inhibitory interneurons that selectively express the transcription factor Engrailed1. Our results show that V1 neurons shape motor outputs during locomotion and are required for generating 'fast' motor bursting. These findings outline an important role for inhibition in regulating the frequency of the locomotor CPG rhythm, and also suggest that V1 neurons may have an evolutionarily conserved role in controlling the speed of vertebrate locomotor movements.
Gosgnach
Simon
S
Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA.
Lanuza
Guillermo M
GM
Butt
Simon J B
SJ
Saueressig
Harald
H
Zhang
Ying
Y
Velasquez
Tomoko
T
Riethmacher
Dieter
D
Callaway
Edward M
EM
Kiehn
Ole
O
Goulding
Martyn
M
D000200:Action Potentials; D000818:Animals; D005136:Eye Proteins / Q000235:genetics; D017353:Gene Deletion; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D007395:Interneurons / Q000502:physiology; D008124:Locomotion / Q000235:genetics / Q000502:physiology*; D051379:Mice; D009046:Motor Neurons / Q000502:physiology*; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors / Q000172:deficiency / Q000235:genetics; D018013:Receptors, Neuropeptide / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics; D013116:Spinal Cord / Q000166:cytology* / Q000502:physiology*; D013997:Time Factors; D019076:Transgenes / Q000235:genetics; D016138:Walking / Q000502:physiology
C080330:En1 protein, mouse; D005136:Eye Proteins; D018398:Homeodomain Proteins; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; D018013:Receptors, Neuropeptide; D012097:Repressor Proteins; C509142:allatostatin receptor, mouse