Claire Wyart graduated from the Ecole Normale Supérieure Ulm in 2000. Under the supervision of Laurent Bourdieu and Didier Chatenay, she obtained her PhD in biophysics and neuroscience from the University of Strasbourg and moved to University of California in Berkeley for her postdoc. In the lab of Udi Isacoff, she developed optical techniques to control activity of neurons remotely in vivo (optogenetics).

The team of Claire Wyart now combines genetics, biophysics, physiology & behavior to understand how sensory inputs are integrated in the spinal cord during development and active locomotion. Her lab discovered that neurons contacting the cerebrospinal fluid (CSF) in the spinal cord are mechanoreceptors detecting curvature of the spinal cord and CSF flow, which modulate the activity of spinal neurons controlling locomotion and posture. We use the transparent zebrafish larva to implement optical methods for manipulating and monitoring neuronal activity in motion. Our work aims to unravel the mechanisms by which interoceptive sensory inputs are integrated throughout life to form the spinal cord, and insure homeostasis in the mature stages.

One critical effort lies in testing the results we obtained in zebrafish in humans.


Neuromodulation in hindbrain and spinal cord

Arousal locomotion is strongly modulated by our inner physiological states. This spontaneous exploratory locomotion reflects the excitability of motor circuits in the spinal cord as well as descending commands from the brain, in particular from the hindbrain. The underlying mechanisms controlling the occurrence of spontaneous locomotion and its natural variability among animals and across physiological states within one animal are not well understood. We are interested in probing neuromodulatory pathways in the hindbrain and spinal cord for setting the frequency of occurrence of locomotion in the context of circadian rhythm, inflammation and feeding.

Modulation of motor circuits via the cerebrospinal fluid

The classical view of spinal cord physiology relies on the fact that motor functions are carried by ventral spinal cord while dorsal spinal cord integrates sensory inputs from the periphery. Up to recently, there was no evidence that the vertebrate spinal cord carried itself sensory functions. Our team has shown evidence for a central sensory motor loop localized in the spinal cord and modulating circuits underlying locomotion and posture. We have evidence that the morphology and molecular markers of this central sensory system is conserved in the mammalian spinal cord.

Mechanosensory feedback to the spinal cord during active locomotion

The contribution of mechanosensory feedback to active locomotion and the nature of underlying spinal circuits remain elusive. We investigate how mechanosensory feedback shapes active locomotion in the zebrafish larva. We find that mechanosensory feedback enhances the recruitment of motor pools during active locomotion. We show that inputs from glutamatergic mechanosensory neurons increase locomotor speed by prolonging fast swimming at the expense of slow swimming during stereotyped acoustic escape responses. Altogether, our efforts reveal the basic principles and circuit diagram underlying speed modulation by mechanosensory feedback in the vertebrate spinal cord.



Mechanosensory feedback enhance speed of locomotion : a novel circuit involved in the spinal cord

Steven Knafo, Kevin Fidelin and co-workers have implemented bioluminescence recordings of motor neurons to reveal the role of mechanosensory feedback on motor neuron recruitment. Accordingly, silencing mechanosensory neurons slows down locomotion by reducing the number of fast oscillations during vestibulo-acoustic escapes. Optogenetic-mediated mapping of synaptic connectivity reveals a monosynaptic connection from excitatory mechanosensory neurons onto V2a interneurons driving fast locomotion in the spinal cord.

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April 1st, 2017: Kevin moves to Columbia University

March 16th, 2017: Kristen moves to the Bormuth lab in UPMC!

March 1st, 2017: Urs starts in Harvard University

March 1st, 2017: Lydia starts in Harvard university

Lydia's article is accepted in Scientific Reports : Congratulations !

Claire is awarded the 2017 prize from the Fondation Scientifique pour l Education et la Recherche

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Claire is awarded in 2016 the New York Stem Cell Foundation Innovator in Neuroscience Award

Claire is a 2016 awardee of the EMBO-Young Investigator Program

Jeff's article is accepted in Current Biology : Congrats !

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Jenna & Kris's article is accepted in Current Biology: Congrats !

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Oscar from the Emiliani lab publishes 3D holographic method for optogenetic applications : Congrats!

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Urs and Andy's article is accepted in Nature Communications: Congrats !

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Kevin's article is accepted in Current Biology : Congrats !

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Lydia's article is published in Frontiers in Neuroanatomy !

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Olivier's article is out in Frontiers in Neural Circuits

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Laura Desban obtains a fourth PhD year from the FRM: congrats !