Semaphorin/neuropilin signaling influences the positioning of migratory neural crest cells within the hindbrain region of the chick
Semaphorin/neuropilin signaling influences the positioning of migratory neural crest cells within the hindbrain region of the chick
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DOI：
10.1002/dvdy.20258
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发表时间：
2005-04-01
影响因子：
2.5
通讯作者：
Eickholt, BJ
中科院分区：
文献类型：
--
作者：
Osborne, NJ;Begbie, J;Eickholt, BJ
在后脑区域内，神经嵴细胞迁移被组织成三个流，遵循神经上皮分割成不同的菱形隔室。虽然已知神经嵴细胞的流动涉及来自神经上皮的信号，但对这一过程的分子特性知之甚少。在这里，我们已经映射了两个分泌的III类脑信号蛋白，脑信号蛋白（Sema）3A和Sema 3F，在对应于鸡后脑区域内的神经嵴细胞迁移的时间点的信号成分的表达。两种脑信号蛋白在菱形球内以邻近无嵴间充质的水平表达，并且神经嵴细胞对脑信号蛋白活性所必需的受体组分的表达表明了限制神经嵴细胞迁移的功能。通过使用珠植入和电穿孔在卵，我们定义了两个脑信号蛋白在维持神经嵴细胞流接近神经管的作用。通过可溶性神经纤毛蛋白-Fc的表达减弱脑信号蛋白信号传导导致神经嵴细胞侵入通常无嵴的相邻间充质区域。在脑信号蛋白信号传导改变后，特定神经嵴细胞群的丢失或误导也影响颅感觉神经节的整合。因此，由后脑神经上皮表达和分泌的Sema 3A和3F有助于神经嵴细胞在神经管附近的适当定位，这是随后在后脑区域内建立神经元连接的关键过程。(c)2005 Wiley-Liss，Inc.
Within the hindbrain region, neural crest cell migration is organized into three streams that follow the segmentation of the neuroepithelium into distinct rhombomeric compartments. Although the streaming of neural crest cells is known to involve signals derived from the neuroepithelium, the molecular properties underlying this process are poorly understood. Here, we have mapped the expression of the signaling component of two secreted class III Semaphorins, Semaphorin (Sema) 3A and Sema 3F, at time points that correspond to neural crest cell migration within the hindbrain region of the chick. Both Semaphorins are expressed within rhombomeres at levels adjacent to crest-free mesenchyme and expression of the receptor components essential for Semaphorin activity by neural crest cells suggests a function in restricting neural crest cell migration. By using bead implantation and electroporation in ovo, we define a role for both Semaphorins in the maintenance of neural crest cell streams in proximity to the neural tube. Attenuation of Semaphorin signaling by expression of soluble Neuropilin-Fc resulted in neural crest cells invading adjacent mesenchymal territories that are normally crest-free. The loss or misguidance of specific neural crest cell populations after changes in Semaphorin signaling also affects the integration of the cranial sensory ganglia. Thus, Sema 3A and 3F, expressed and secreted by the hindbrain neuroepithelium contributes to the appropriate positioning of neural crest cells in proximity to the neural tube, a process crucial for the subsequent establishment of neuronal connectivity within the hindbrain region. (c) 2005 Wiley-Liss, Inc.