Current Principles of Motor Control, with Special Reference to Vertebrate Locomotion

Physiological Reviews, Journal Year: 2019, Volume and Issue: 100(1), P. 271 - 320

Published: Sept. 12, 2019

The vertebrate control of locomotion involves all levels the nervous system from cortex to spinal cord. Here, we aim cover main aspects this complex behavior, operation microcircuits in cord systems and behavioral extend mammalian basic undulatory movements lamprey fish. cellular basis propulsion represents core system, it central pattern generator networks (CPGs) controlling timing different muscles, sensory compensation for perturbations, brain stem command level activity CPGs speed locomotion. forebrain particular basal ganglia are involved determining which motor programs should be recruited at a given point time can both initiate stop locomotor activity. propulsive needs integrated with postural maintain body orientation. Moreover, need steered so that subject approaches goal episode, or avoids colliding elements environment simply escapes high speed. These will covered review.

Language: Английский

---

Homeobox genes and the specification of neuronal identity

Nature reviews. Neuroscience, Journal Year: 2021, Volume and Issue: 22(10), P. 627 - 636

Published: Aug. 26, 2021

Language: Английский

---

Multiple Rhythm-Generating Circuits Act in Tandem with Pacemaker Properties to Control the Start and Speed of Locomotion

Neuron, Journal Year: 2020, Volume and Issue: 105(6), P. 1048 - 1061.e4

Published: Jan. 22, 2020

Language: Английский

---

Single cell atlas of spinal cord injury in mice reveals a pro-regenerative signature in spinocerebellar neurons

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Sept. 26, 2022

Abstract After spinal cord injury, tissue distal to the lesion contains undamaged cells that could support or augment recovery. Targeting these requires a clearer understanding of their injury responses and capacity for repair. Here, we use single nucleus RNA sequencing profile how each cell type in lumbar changes after thoracic mice. We present an atlas dynamic across dozens types acute, subacute, chronically injured cord. Using this resource, find rare neurons express signature regeneration response including major population represent spinocerebellar projection neurons. characterize anatomically observed axonal sparing, outgrowth, remodeling cerebellum. Together, work provides key resource studying cellular uncovers spontaneous plasticity neurons, uncovering potential candidate targeted therapy.

Language: Английский

---

Neurotransmitter phenotype switching by spinal excitatory interneurons regulates locomotor recovery after spinal cord injury

Nature Neuroscience, Journal Year: 2022, Volume and Issue: 25(5), P. 617 - 629

Published: May 1, 2022

Abstract Severe spinal cord injury in adults leads to irreversible paralysis below the lesion. However, adult rodents that received a complete thoracic lesion just after birth demonstrate proficient hindlimb locomotion without input from brain. How achieves such striking plasticity remains unknown. In this study, we found prompts neurotransmitter switching of spatially defined excitatory interneurons an inhibitory phenotype, promoting inhibition at synapses contacting motor neurons. contrast, neonatal maintains phenotype glutamatergic and causes synaptic sprouting facilitate excitation. Furthermore, genetic manipulation mimic observed abrogates autonomous locomotor functionality neonatally injured mice. comparison, attenuating improves capacity injury. Together, these data steers recovery

Language: Английский

---

Spinal Interneurons: Diversity and Connectivity in Motor Control

Annual Review of Neuroscience, Journal Year: 2023, Volume and Issue: 46(1), P. 79 - 99

Published: Feb. 28, 2023

The spinal cord is home to the intrinsic networks for locomotion. An animal in which has been fully severed from brain can still produce rhythmic, patterned locomotor movements as long some excitatory drive provided, such physical, pharmacological, or electrical stimuli. Yet it remains a challenge define underlying circuitry that produces these because contains wide variety of neuron classes whose patterns interconnectivity are poorly understood. Computational models locomotion accordingly rely on untested assumptions about network element identity and connectivity. In this review, we consider neurons, their interconnectivity, significance circuit connections along axis cord. We suggest several lines analysis move toward definitive understanding network.

Language: Английский

---

A dynamic role for dopamine receptors in the control of mammalian spinal networks

Scientific Reports, Journal Year: 2020, Volume and Issue: 10(1)

Published: Oct. 2, 2020

Abstract Dopamine is well known to regulate movement through the differential control of direct and indirect pathways in striatum that express D 1 2 receptors respectively. The spinal cord also expresses all dopamine receptors; however, how specific network output mammals poorly understood. We explore receptor-specific mechanisms underlie dopaminergic neonatal mice during changes excitability. During spontaneous activity, which a characteristic developing networks operating low excitability state, we found primarily inhibitory. uncover an excitatory -mediated effect on motoneurons involves co-activation with receptors. Critically, these actions require higher concentrations dopamine; analysis neonates indicates endogenous levels are low. Because low, this pathway likely physiologically-silent at stage development. In contrast, inhibitory dopamine, physiological mediated by parallel activation , 3 4 α reproduced when increased blocking reuptake metabolism. provide evidence support dedicated components controlled reminiscent classic within striatum. These results indicate state important factor dictates therefore dose-dependent neuromodulators advances our understanding neural under dynamically changing

Language: Английский

---

The CPGs for Limbed Locomotion–Facts and Fiction

International Journal of Molecular Sciences, Journal Year: 2021, Volume and Issue: 22(11), P. 5882 - 5882

Published: May 30, 2021

The neuronal networks that generate locomotion are well understood in swimming animals such as the lamprey, zebrafish and tadpole. controlling tetrapods remain, however, still enigmatic with an intricate motor pattern required for control of entire limb during support, lift off, flexion phase, most demandingly when makes contact ground again. It is clear inhibition occurs between bursts each step cycle produced by V2b V1 interneurons, a deletion these interneurons leads to synchronous flexor–extensor bursting. ability rhythmic bursting distributed over all segments comprising part central generator network (CPG). unclear how generated; Shox2, V2a HB9 do contribute. To deduce possible organization locomotor CPG, simulations have been elaborated. has simulated considerable detail composed unit burst generators; one group close synergistic muscle groups at joint. This model can reproduce complex constant phase shortened extensor speed increases. Moreover, versatile both forward backward locomotion.

Language: Английский

---

The Prop1-like homeobox gene unc-42 specifies the identity of synaptically connected neurons

eLife, Journal Year: 2021, Volume and Issue: 10

Published: June 24, 2021

Many neuronal identity regulators are expressed in distinct populations of cells the nervous system, but their function is often analyzed only specific isolated cellular contexts, thereby potentially leaving overarching themes gene undiscovered. We show here that Caenorhabditis elegans Prop1-like homeobox unc-42 15 sensory, inter- and motor neuron classes throughout entire C. system. Strikingly, all expressing synaptically interconnected, prompting us to investigate whether controls functional properties this circuit perhaps also assembly these neurons into circuitry. found defines routes communication between interconnected by controlling expression neurotransmitter pathway genes, receptors, neuropeptides, neuropeptide receptors. Anatomical analysis mutant animals reveals defects axon pathfinding synaptic connectivity, paralleled molecules involved pathfinding, cell-cell recognition, connectivity. conclude establishes circuitry acting as a terminal selector functionally connected types. identify number additional transcription factors propose selectors may ‘circuit organizer factors’ control hypothesize such organizational be reflective not ontogenetic, phylogenetic trajectories establishment.

Language: Английский

---

The enteric nervous system of the C. elegans pharynx is specified by the Sine oculis-like homeobox gene ceh-34

eLife, Journal Year: 2022, Volume and Issue: 11

Published: March 24, 2022

Overarching themes in the terminal differentiation of enteric nervous system, an autonomously acting unit animal systems, have so far eluded discovery. We describe here overall regulatory logic system nematode Caenorhabditis elegans that resides within foregut (pharynx) worm. A C. homolog Drosophila Sine oculis homeobox gene, ceh-34 , is expressed all 14 classes interconnected pharyngeal neurons from their birth throughout life time, but no other neuron type entire animal. Constitutive and temporally controlled removal shows required to initiate maintain type-specific program classes, including circuit assembly. Through additional genetic loss function analysis, we show each class, cooperates with different homeodomain transcription factors individuate distinct classes. Our analysis underscores critical role genes neuronal identity specification links them control assembly system. Together simplicity as well its by a homolog, our findings invite speculations about early evolution systems.

Language: Английский

---