title: Intraspinal Sensory Neurons Provide Powerful Inhibition to Motor Circuits Ensuring Postural Control during Locomotion.
abstract: In the vertebrate spinal cord, cerebrospinal fluid-contacting neurons (CSF-cNs) are GABAergic neurons whose functions are only beginning to unfold. Recent evidence indicates that CSF-cNs detect local spinal bending and relay this mechanosensory feedback information to motor circuits, yet many CSF-cN targets remain unknown. Using optogenetics, patterned illumination, and in vivo electrophysiology, we show here that CSF-cNs provide somatic inhibition to fast motor neurons and excitatory sensory interneurons involved in the escape circuit. Ventral CSF-cNs respond to longitudinal spinal contractions and induce large inhibitory postsynaptic currents (IPSCs) sufficient to silence spiking of their targets. Upon repetitive stimulation, these IPSCs promptly depress, enabling the mechanosensory response to the first bend to be the most effective. When CSF-cNs are silenced, postural control is compromised, resulting in rollovers during escapes. Altogether, our data demonstrate how GABAergic sensory neurons provide powerful inhibitory feedback to the escape circuit to maintain balance during active locomotion.
authors.affiliation: Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France.
authors.forename: Jeffrey Michael
authors.initials: JM
authors.lastname: Hubbard
authors.affiliation: Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France.
authors.forename: Urs Lucas
authors.initials: UL
authors.lastname: Böhm
authors.affiliation: Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France.
authors.forename: Andrew
authors.initials: A
authors.lastname: Prendergast
authors.affiliation: Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France.
authors.forename: Po-En Brian
authors.initials: PB
authors.lastname: Tseng
authors.affiliation: Department of Genetics and Evolution, School of Biological Sciences, The University of Adelaide, Adelaide, SA 5005, Australia.
authors.forename: Morgan
authors.initials: M
authors.lastname: Newman
authors.affiliation: Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University Paris 06, 75005 Paris, France.
authors.forename: Caleb
authors.initials: C
authors.lastname: Stokes
authors.affiliation: Institut du Cerveau et de la Moelle Épinière, Hôpital Pitié Salpêtrière, 47 Boulevard de l'Hôpital, 75013 Paris, France; INSERM UMRS 1127, 75013 Paris, France; CNRS UMR 7225, 75005 Paris, France; UPMC University 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; D059330:GABAergic Neurons / Q000502:physiology; D007395:Interneurons / Q000502:physiology; D009046:Motor Neurons / Q000502:physiology; D011187:Posture; D011984:Sensory Receptor Cells / Q000502:physiology*; D013550:Swimming; D015027:Zebrafish / Q000502:physiology*
keywords: CSF-cN; GABAergic sensory neuron; connectome; escape behavior; optogenetics; posture; sensory-motor feedback; spinal cord; zebrafish