Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control
The spinal cord contains a diverse array of interneurons that govern motor output. Traditionally, models of spinal circuits have emphasized the role of inhibition in enforcing reciprocal alternation between left and right sides or flexors and extensors. However, recent work has shown that inhibition...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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eLife Sciences Publications Ltd
2019-07-01
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| Series: | eLife |
| Subjects: | |
| Online Access: | https://elifesciences.org/articles/47837 |
| _version_ | 1811236818264260608 |
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| author | Rebecca A Callahan Richard Roberts Mohini Sengupta Yukiko Kimura Shin-ichi Higashijima Martha W Bagnall |
| author_facet | Rebecca A Callahan Richard Roberts Mohini Sengupta Yukiko Kimura Shin-ichi Higashijima Martha W Bagnall |
| author_sort | Rebecca A Callahan |
| collection | DOAJ |
| description | The spinal cord contains a diverse array of interneurons that govern motor output. Traditionally, models of spinal circuits have emphasized the role of inhibition in enforcing reciprocal alternation between left and right sides or flexors and extensors. However, recent work has shown that inhibition also increases coincident with excitation during contraction. Here, using larval zebrafish, we investigate the V2b (Gata3+) class of neurons, which contribute to flexor-extensor alternation but are otherwise poorly understood. Using newly generated transgenic lines we define two stable subclasses with distinct neurotransmitter and morphological properties. These V2b subclasses synapse directly onto motor neurons with differential targeting to speed-specific circuits. In vivo, optogenetic manipulation of V2b activity modulates locomotor frequency: suppressing V2b neurons elicits faster locomotion, whereas activating V2b neurons slows locomotion. We conclude that V2b neurons serve as a brake on axial motor circuits. Together, these results indicate a role for ipsilateral inhibition in speed control. |
| first_indexed | 2024-04-12T12:14:40Z |
| format | Article |
| id | doaj.art-814e76c7bafb4d759b95f9b800a14226 |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-12T12:14:40Z |
| publishDate | 2019-07-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-814e76c7bafb4d759b95f9b800a142262022-12-22T03:33:28ZengeLife Sciences Publications LtdeLife2050-084X2019-07-01810.7554/eLife.47837Spinal V2b neurons reveal a role for ipsilateral inhibition in speed controlRebecca A Callahan0Richard Roberts1Mohini Sengupta2https://orcid.org/0000-0002-5234-8258Yukiko Kimura3https://orcid.org/0000-0001-8381-8622Shin-ichi Higashijima4https://orcid.org/0000-0001-6350-4992Martha W Bagnall5https://orcid.org/0000-0003-2102-6165Department of Neuroscience, Washington University School of Medicine, St Louis, United StatesDepartment of Neuroscience, Washington University School of Medicine, St Louis, United StatesDepartment of Neuroscience, Washington University School of Medicine, St Louis, United StatesNational Institute for Basic Biology, Okazaki, JapanNational Institute for Basic Biology, Okazaki, JapanDepartment of Neuroscience, Washington University School of Medicine, St Louis, United StatesThe spinal cord contains a diverse array of interneurons that govern motor output. Traditionally, models of spinal circuits have emphasized the role of inhibition in enforcing reciprocal alternation between left and right sides or flexors and extensors. However, recent work has shown that inhibition also increases coincident with excitation during contraction. Here, using larval zebrafish, we investigate the V2b (Gata3+) class of neurons, which contribute to flexor-extensor alternation but are otherwise poorly understood. Using newly generated transgenic lines we define two stable subclasses with distinct neurotransmitter and morphological properties. These V2b subclasses synapse directly onto motor neurons with differential targeting to speed-specific circuits. In vivo, optogenetic manipulation of V2b activity modulates locomotor frequency: suppressing V2b neurons elicits faster locomotion, whereas activating V2b neurons slows locomotion. We conclude that V2b neurons serve as a brake on axial motor circuits. Together, these results indicate a role for ipsilateral inhibition in speed control.https://elifesciences.org/articles/47837spinal cordlocomotioncircuitryinhibition |
| spellingShingle | Rebecca A Callahan Richard Roberts Mohini Sengupta Yukiko Kimura Shin-ichi Higashijima Martha W Bagnall Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control eLife spinal cord locomotion circuitry inhibition |
| title | Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control |
| title_full | Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control |
| title_fullStr | Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control |
| title_full_unstemmed | Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control |
| title_short | Spinal V2b neurons reveal a role for ipsilateral inhibition in speed control |
| title_sort | spinal v2b neurons reveal a role for ipsilateral inhibition in speed control |
| topic | spinal cord locomotion circuitry inhibition |
| url | https://elifesciences.org/articles/47837 |
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