Development of oculomotor axon projections in the chick embryo
Development of oculomotor axon projections in the chick embryo
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DOI：
10.1002/cne.20071
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发表时间：
2004-05-03
影响因子：
2.5
通讯作者：
Guthrie, S
中科院分区：
文献类型：
--
作者：
Chilton, JK;Guthrie, S
眼外肌的神经支配模式在高等脊椎动物物种中高度保守，并介导复杂的视觉过程。动眼神经发育缺陷通常会导致斜视，即眼睛错位，可导致部分失明。虽然它已经从临床的角度进行了深入的研究，但对该系统如何在胚胎中发育知之甚少。因此，我们已经映射的发育眼神经（OMN）在鸡胚中使用共聚焦显微镜。我们发现，OMN的发展遵循一系列刻板的步骤，在空间和时间上受到严格的监管。OMN最初生长超过其三个目标，以神经支配其远端目标，腹斜肌，只是后来形成分支到更近端的肌肉。我们还调查了时空方面的不寻常的对侧迁移的一个亚群的眼神经元，通过使用分子标记物，并发现了脑信号蛋白轴突导向分子和它们的受体，neuropilins，表达在离散的亚核在此迁移。最后，我们建立了一个胚胎学模型的杜安回缩综合征（DRS），斜视的一种形式，其中OMN被认为是异常支配外直肌，外展神经的正常目标。通过消融菱形第5和第6，因此外展神经，我们模仿了一个建议的眼神经缺损发生在DRS。我们发现，外展神经的缺乏是不足以产生这种不适当的神经支配，所以需要其他因素来解释DRS。（C）2004威利-利斯公司。
The pattern of innervation of the extraocular muscles is highly conserved across higher vertebrate species and mediates sophisticated visuomotor processes. Defects in oculomotor development often lead to strabismus, a misalignment of the eyes that can cause partial blindness. Although it has been intensively studied from a clinical perspective, relatively little is known about how the system develops embryonically. We have therefore mapped the development of the oculomotor nerve (OMN) in chick embryos by using confocal microscopy. We show that OMN development follows a series of stereotyped steps that are tightly regulated in space and time. The OMN initially grows past three of its targets to innervate its distal target, the ventral oblique muscle, only later forming branches to the more proximal muscles. We have also investigated spatiotemporal aspects of the unusual contralateral migration of a subpopulation of oculomotor neurons by using molecular markers and have found the semaphorin axon guidance molecules and their receptors, the neuropilins, to be expressed in discrete subnuclei during this migration. Finally, we have created an embryological model of Duane retraction syndrome (DRS), a form of strabismus in which the OMN is believed to innervate aberrantly the lateral rectus, the normal target of the abducens nerve. By ablating rhombomeres 5 and 6 and hence the abducens, we have mimicked a proposed oculomotor deficit occurring in DRS. We find that the absence of the abducens nerve is not sufficient to produce this inappropriate innervation, so other factors are required to explain DRS. (C) 2004 Wiley-Liss, Inc.