Positional Strategies for Connection Specificity and Synaptic Organization in Spinal Sensory-Motor Circuits
Positional Strategies for Connection Specificity and Synaptic Organization in Spinal Sensory-Motor Circuits
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DOI：
10.1016/j.neuron.2019.04.008
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发表时间：
2019-06-19
期刊：
影响因子：
16.2
通讯作者：
Ng, David
中科院分区：
文献类型：
--
作者：
Balaskas, Nikolaos;Abbott, L. F.;Ng, David
脊髓中的本体感觉轴突与运动神经元伙伴形成选择性连接，但赋予这种选择性的策略仍不确定。我们发现，肌肉特异性感觉轴突沿着地形组织的角轨迹投射到运动神经元，运动池表现出不同的树突树突。基于轴-树突相互作用的空间约束，我们提出了可以解释感觉-运动连接和突触组织的位置策略。这些策略依赖于两个模式原则。首先，轴-树突的重叠程度减少了潜在的突触后伙伴的数量。其次，当感觉轴突与多个具有重叠树突树突的运动池相交时，轴突-树突通路的小角度与突触簇的形成密切相关，这使得连接具有特异性。我们的研究确定了位置策略在脊髓感觉-运动回路的组织中具有突出的作用。
Proprioceptive sensory axons in the spinal cord form selective connections with motor neuron partners, but the strategies that confer such selectivity remain uncertain. We show that muscle-specific sensory axons project to motor neurons along topographically organized angular trajectories and that motor pools exhibit diverse dendritic arbors. On the basis of spatial constraints on axo-dendritic interactions, we propose positional strategies that can account for sensory-motor connectivity and synaptic organization. These strategies rely on two patterning principles. First, the degree of axo-dendritic overlap reduces the number of potential post-synaptic partners. Second, a close correlation between the small angle of axo-dendritic approach and the formation of synaptic clusters imposes specificity of connections when sensory axons intersect multiple motor pools with overlapping dendritic arbors. Our study identifies positional strategies with prominent roles in the organization of spinal sensory-motor circuits.