Multifold increase in spinal inhibitory cell types with emergence of limb movement

article Multifold increase in spinal inhibitory cell types with emergence of limb movement published yes David Vijatovic author cf391e77-ec3c-11ea-a124-d69323410b58 Florina Alexandra Toma author 2f73f876-f128-11eb-9611-b96b5a30cb0e Y Ignatyev author Zoe P Harrington author a8144562-32c9-11ee-b5ce-d9800628bda20009-0008-0158-4032 Christoph M Sommer author 4DF26D8C-F248-11E8-B48F-1D18A9856A870000-0003-1216-9105 Robert Hauschild author 4E01D6B4-F248-11E8-B48F-1D18A9856A870000-0001-9843-3522 Matthijs Geert Smits author 7a231d52-e216-11ee-a0bb-8acd55f8f1f0 Marco Dalla Vecchia author 02a7a869-ff06-11ed-a87f-86649d6077e5 Alexandra J. Trevisan author Phillip Chapman author Mara Julseth author 1cf464b2-dc7d-11ea-9b2f-f9b1aa9417d1 Susan Brenner-Morton author Mariano I. Gabitto author Jeremy S. Dasen author Jay B. Bikoff author Lora Beatrice Jaeger Sweeney author 56BE8254-C4F0-11E9-8E45-0B23E66974250000-0001-9242-5601 LoSw department GradSch department TiVo department Bio department NiBa department Development and Evolution of Tetrapod Motor Circuits project Stem Cell Modulation in Neural Development and Regeneration/ P14-Swim-to-limb transition: cell type to connection diversity project Tools for automation and feedback microscopy project Development of V1 interneuron diversity during swim-to-walk transition of Xenopus metamorphosis project As vertebrates transitioned from water to land, locomotion shifted from undulatory swimming to limb-based movement. How spinal circuits and their cell types evolved to support this transition remains unclear. We leverage frog metamorphosis, which recapitulates this transition within a single organism, to define how spinal circuits generate aquatic versus terrestrial motor patterns. At swim stages, spinal architecture is uniform, with a transcriptionally and anatomically homogeneous motor and interneurons. As limbs develop and their movement complexifies, spinal circuits expand in neuron number and subtype diversity. This expansion is most pronounced for V1 inhibitory neurons, which increase ∼70-fold and diversify into transcriptionally distinct subtypes. Disrupting transcription factors defining emerging motor and V1 populations reveals molecular segregation between swim and limb circuits, highlighting the role of subtype diversity in motor coordination. A multifold increase in inhibitory neuron diversity thus underlies the tail-to-limb locomotor transition, providing a framework for spinal circuit adaptation during vertebrate evolution. https://research-explorer.ista.ac.at/download/21746/21795/2026_CellReports_Vijatovic.pdf application/pdfno Elsevier2026 eng Cell Reports 2639-1856 2211-1247 41964955 10.1016/j.celrep.2026.117227 454 Vijatovic, David, Florina Alexandra Toma, Y Ignatyev, Zoe P Harrington, Christoph M Sommer, Robert Hauschild, Matthijs Geert Smits, et al. “Multifold Increase in Spinal Inhibitory Cell Types with Emergence of Limb Movement.” Cell Reports. Elsevier, 2026. <a href="https://doi.org/10.1016/j.celrep.2026.117227">https://doi.org/10.1016/j.celrep.2026.117227</a>. Vijatovic D, Toma FA, Ignatyev Y, Harrington ZP, Sommer CM, Hauschild R, Smits MG, Dalla Vecchia M, Trevisan AJ, Chapman P, Julseth M, Brenner-Morton S, Gabitto MI, Dasen JS, Bikoff JB, Sweeney LB. 2026. Multifold increase in spinal inhibitory cell types with emergence of limb movement. Cell Reports. 45(4), 117227. Vijatovic, David, et al. “Multifold Increase in Spinal Inhibitory Cell Types with Emergence of Limb Movement.” Cell Reports, vol. 45, no. 4, 117227, Elsevier, 2026, doi:<a href="https://doi.org/10.1016/j.celrep.2026.117227">10.1016/j.celrep.2026.117227</a>. D. Vijatovic, F.A. Toma, Y. Ignatyev, Z.P. Harrington, C.M. Sommer, R. Hauschild, M.G. Smits, M. Dalla Vecchia, A.J. Trevisan, P. Chapman, M. Julseth, S. Brenner-Morton, M.I. Gabitto, J.S. Dasen, J.B. Bikoff, L.B. Sweeney, Cell Reports 45 (2026). D. Vijatovic et al., “Multifold increase in spinal inhibitory cell types with emergence of limb movement,” Cell Reports, vol. 45, no. 4. Elsevier, 2026. Vijatovic, D., Toma, F. A., Ignatyev, Y., Harrington, Z. P., Sommer, C. M., Hauschild, R., … Sweeney, L. B. (2026). Multifold increase in spinal inhibitory cell types with emergence of limb movement. Cell Reports. Elsevier. <a href="https://doi.org/10.1016/j.celrep.2026.117227">https://doi.org/10.1016/j.celrep.2026.117227</a> Vijatovic D, Toma FA, Ignatyev Y, et al. Multifold increase in spinal inhibitory cell types with emergence of limb movement. Cell Reports. 2026;45(4). doi:<a href="https://doi.org/10.1016/j.celrep.2026.117227">10.1016/j.celrep.2026.117227</a> 217462026-04-19T22:07:43Z2026-05-04T12:27:06Z