Facial Visceral Motor Neurons Display Specific Rhombomere Origin and Axon Pathfinding Behavior in the Chick
Facial Visceral Motor Neurons Display Specific Rhombomere Origin and Axon Pathfinding Behavior in the Chick
复制标题
面部内脏运动神经元在小鸡中表现出特定的菱形起源和轴突寻路行为
作者：
John Jacob;S. Guthrie
在鸡胚胎中，面部运动神经元包括鳃运动亚群和内脏运动亚群，分别支配鳃肌和副交感神经节。尽管已知面部运动神经元在后脑菱形核 4 (r4) 和 r5 内发育，但鳃运动神经元和内脏运动神经元亚群的确切起源尚不清楚。我们利用轴突追踪和菱形移植在鹌鹑雏鸡嵌合体中研究了这些运动神经元的组织和轴突寻路。我们的结果表明，绝大多数鳃运动神经元起源于 r4，但这些神经元的一组经历了从 r4 到 r5 的尾部迁移。相比之下，内脏运动神经元仅在 r5 中发育。我们发现面部内脏运动神经元的一个显着特性是其轴突在异位移植后导航回周围适当的神经节目标的能力。这些结果补充了之前的研究，其中异位面部鳃运动神经元将轴突发送到正确的鳃弓目标。相比之下，当三叉神经鳃运动神经元异位移植时，我们发现它们无法正确寻路，而是投射到不合适的目标区域。因此，面部和三叉神经运动神经元群体具有不同的轴突寻路特征。
In the chick embryo, facial motor neurons comprise branchiomotor and visceral motor subpopulations, which innervate branchial muscles and parasympathetic ganglia, respectively. Although facial motor neurons are known to develop within hindbrain rhombomere 4 (r4) and r5, the precise origins of branchiomotor and visceral motor neuron subpopulations are unclear. We investigated the organization and axon pathfinding of these motor neurons using axonal tracing and rhombomere transplantation in quail-chick chimeras. Our results show that a large majority of branchiomotor neurons originate in r4 but that a cohort of these neurons undergoes a caudal migration from r4 into r5. By contrast, visceral motor neurons develop exclusively in r5. We found that a striking property of facial visceral motor neurons is the ability of their axons to navigate back to appropriate ganglionic targets in the periphery after heterotopic transplantation. These results complement previous studies in which heterotopic facial branchiomotor neurons sent axons to their correct, branchial arch, target. By contrast, when trigeminal branchiomotor neurons were transplanted heterotopically, we found that they were unable to pathfind correctly, and instead projected to an inappropriate target region. Thus, facial and trigeminal motor neuron populations have different axon pathfinding characteristics.
通过靶标衍生的神经营养因子减少体内自然发生的运动神经元死亡。
DOI：
10.1126/science.3363373
发表时间：
1988
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Oppenheim,RW;Haverkamp,LJ;Prevette,D;McManaman,JL;Appel,SH
通讯作者：
Appel,SH