Chapman Phillip D, Kulkarni Anand S, Trevisan Alexandra J, Han Katie, Hinton Jennifer M, Deltuvaite Paulina, Fenno Lief E, Ramakrishnan Charu, Patton Mary H, Schwarz Lindsay A, Zakharenko Stanislav S, Deisseroth Karl, Bikoff Jay B
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
Department of Neuroscience, University of Texas at Austin, Austin, TX 78712, USA; Department of Psychiatry & Behavioral Sciences, University of Texas Dell Medical School, Austin, TX 78712, USA.
Neuron. 2025 Feb 19;113(4):524-538.e6. doi: 10.1016/j.neuron.2024.11.019. Epub 2024 Dec 23.
Motor output results from the coordinated activity of neural circuits distributed across multiple brain regions that convey information to the spinal cord via descending motor pathways. Yet the organizational logic through which supraspinal systems target discrete components of spinal motor circuits remains unclear. Here, using viral transsynaptic tracing along with serial two-photon tomography, we have generated a whole-brain map of monosynaptic inputs to spinal V1 interneurons, a major inhibitory population involved in motor control. We identified 26 distinct brain structures that directly innervate V1 interneurons, spanning medullary and pontine regions in the hindbrain as well as cortical, midbrain, cerebellar, and neuromodulatory systems. Moreover, we identified broad but biased input from supraspinal systems onto V1 and V1 neuronal subsets. Collectively, these studies reveal elements of biased connectivity and convergence in descending inputs to molecularly distinct interneuron subsets and provide an anatomical foundation for understanding how supraspinal systems influence spinal motor circuits.
运动输出源于分布在多个脑区的神经回路的协同活动，这些神经回路通过下行运动通路将信息传递到脊髓。然而，脊髓上系统针对脊髓运动回路离散成分的组织逻辑仍不清楚。在这里，我们利用病毒跨突触示踪技术结合串行双光子断层扫描，生成了脊髓V1中间神经元单突触输入的全脑图谱，V1中间神经元是参与运动控制的主要抑制性细胞群。我们确定了26个直接支配V1中间神经元的不同脑结构，涵盖后脑的延髓和脑桥区域以及皮质、中脑、小脑和神经调节系统。此外，我们确定了脊髓上系统对V1和V1神经元亚群的广泛但有偏向性的输入。总体而言，这些研究揭示了下行输入到分子上不同的中间神经元亚群中的偏向性连接和汇聚的要素，并为理解脊髓上系统如何影响脊髓运动回路提供了解剖学基础。
