V3 Interneurons Are Active and Recruit Spinal Motor Neurons during In Vivo Fictive Swimming in Larval Zebrafish

Timothy D. Wiggin, Jacob E. Montgomery, Amanda J. Brunick, Jack H. Peck, Mark A. Masino

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Survival for vertebrate animals is dependent on the ability to successfully find food, locate a mate, and avoid predation. Each of these behaviors requires motor control, which is set by a combination of kinematic proper-ties. For example, the frequency and amplitude of motor output combine in a multiplicative manner to determine features of locomotion such as distance traveled, speed, force (thrust), and vigor. Although there is a good understanding of how different populations of excitatory spinal interneurons establish locomotor fre-quency, there is a less thorough mechanistic understanding for how locomotor amplitude is established. Recent evidence indicates that locomotor amplitude is regulated in part by a subset of functionally and mor-phologically distinct V2a excitatory spinal interneurons (Type II, nonbursting) in larval and adult zebrafish. Here, we provide direct evidence that most V3 interneurons (V3-INs), which are a developmentally and genetically defined population of ventromedial glutamatergic spinal neurons, are active during fictive swimming. We also show that elimination of the spinal V3-IN population reduces the proportion of active motor neurons (MNs) during fictive swimming but does not alter the range of locomotor frequencies produced. These data are consistent with V3-INs providing excitatory drive to spinal MNs during swimming in larval zebrafish and may contribute to the production of locomotor amplitude independently of locomotor frequency.

Original languageEnglish (US)
Article numberENEURO.0476-21.2022
Issue number2
StatePublished - Mar 1 2022

Bibliographical note

Funding Information:
This work was supported by National Institutes of Health Grants R01 NS065054 (to M.A.M.), R01 NS094176 (to M.A.M.), F31 NS083110 (to T.D.W.), and R25 NS083059; Regenerative Medicine Minnesota Grant RMM 091718 DS 006 (J.E.M.); Grant-in-Aid of Research, Artistry, and Scholarship (M.A.M.), and the University of Minnesota Foundation Bridge Award B-0621-01 (to M.A.M.). *T.D.W. and J.E.M. contributed equally to this work and share first authorship. T. D. Wiggin’s present address: Vizgen, Cambridge, MA 02138.

Publisher Copyright:
© 2022 Wiggin et al.


  • locomotion
  • motor neuron recruitment
  • spinal interneuron
  • zebrafish
  • Locomotion/physiology
  • Animals
  • Interneurons/physiology
  • Motor Neurons/physiology
  • Zebrafish
  • Spinal Cord/physiology
  • Swimming/physiology
  • Larva/physiology

PubMed: MeSH publication types

  • Research Support, Non-U.S. Gov't
  • Journal Article
  • Research Support, N.I.H., Extramural


Dive into the research topics of 'V3 Interneurons Are Active and Recruit Spinal Motor Neurons during In Vivo Fictive Swimming in Larval Zebrafish'. Together they form a unique fingerprint.

Cite this