title: State-Dependent Modulation of Locomotion by GABAergic Spinal Sensory Neurons.
abstract: The cerebrospinal fluid (CSF) constitutes an interface through which chemical cues can reach and modulate the activity of neurons located at the epithelial boundary within the entire nervous system. Here, we investigate the role and functional connectivity of a class of GABAergic sensory neurons contacting the CSF in the vertebrate spinal cord and referred to as CSF-cNs. The remote activation of CSF-cNs was shown to trigger delayed slow locomotion in the zebrafish larva, suggesting that these cells modulate components of locomotor central pattern generators (CPGs). Combining anatomy, electrophysiology, and optogenetics in vivo, we show that CSF-cNs form active GABAergic synapses onto V0-v glutamatergic interneurons, an essential component of locomotor CPGs. We confirmed that activating CSF-cNs at rest induced delayed slow locomotion in the fictive preparation. In contrast, the activation of CSF-cNs promptly inhibited ongoing slow locomotion. Moreover, selective activation of rostral CSF-cNs during ongoing activity disrupted rostrocaudal propagation of descending excitation along the spinal cord, indicating that CSF-cNs primarily act at the premotor level. Altogether, our results demonstrate how a spinal GABAergic sensory neuron can tune the excitability of locomotor CPGs in a state-dependent manner by projecting onto essential components of the excitatory premotor pool.
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France.
authors.forename: Kevin
authors.initials: K
authors.lastname: Fidelin
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France; Museum National d'Histoire Naturelle, 75005 Paris, France.
authors.forename: Lydia
authors.initials: L
authors.lastname: Djenoune
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France.
authors.forename: Caleb
authors.initials: C
authors.lastname: Stokes
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France.
authors.forename: Andrew
authors.initials: A
authors.lastname: Prendergast
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France.
authors.forename: Johanna
authors.initials: J
authors.lastname: Gomez
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Baradel
authors.affiliation: UPMC Univ Paris 06, 75005 Paris, France; Institut Curie, CNRS UMR 3215, INSERM U934, 75005 Paris, France.
authors.forename: Filippo
authors.initials: F
authors.lastname: Del Bene
authors.affiliation: Institut du Cerveau et de la Moelle épinière (ICM), 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75013 Paris, France; UPMC Univ Paris 06, 75005 Paris, France. Electronic address: claire.wyart@icm-institute.org.
authors.forename: Claire
authors.initials: C
authors.lastname: Wyart
mesh_terms: D000818:Animals; D002555:Cerebrospinal Fluid / Q000502:physiology; D059330:GABAergic Neurons / Q000502:physiology*; D007395:Interneurons / Q000502:physiology; D008124:Locomotion; D011984:Sensory Receptor Cells / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology; D013569:Synapses / Q000502:physiology; D015027:Zebrafish / Q000502:physiology*