A cluster of cholinergic premotor interneurons modulates mouse locomotor activity
Abstract
Mammalian motor programs are controlled by networks of spinal interneurons that set the rhythm and intensity of motor neuron firing. Motor neurons have long been known to receive prominent “C bouton” cholinergic inputs from spinal interneurons, but the source and function of these synaptic inputs have remained obscure. We show here that the transcription factor Pitx2 marks a small cluster of spinal cholinergic interneurons, V0C neurons, that represents the sole source of C bouton inputs to motor neurons. The activity of these cholinergic interneurons is tightly phase locked with motor neuron bursting during fictive locomotor activity, suggesting a role in the modulation of motor neuron firing frequency. Genetic inactivation of the output of these neurons impairs a locomotor task-dependent increase in motor neuron firing and muscle activation. Thus, V0C interneurons represent a defined class of spinal cholinergic interneurons with an intrinsic neuromodulatory role in the control of locomotor behavior.
Citation
Zagoraiou , L , Akay , T , Martin , J F , Brownstone , R M , Jessell , T M & Miles , G B 2009 , ' A cluster of cholinergic premotor interneurons modulates mouse locomotor activity ' , Neuron , vol. 64 , no. 5 , pp. 645-662 . https://doi.org/10.1016/j.neuron.2009.10.017
Publication
Neuron
Status
Peer reviewed
ISSN
0896-6273Type
Journal article
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.