Homeogenetic neural induction in Xenopus.
Homeogenetic neural induction in Xenopus.
复制标题
非洲爪蟾的同源神经诱导。
DOI：
10.1016/s0012-1606(05)80008-9
复制
发表时间：
1991
影响因子：
2.7
通讯作者：
Grainger,RM
中科院分区：
文献类型：
--
作者：
Servetnick,M;Grainger,RM
神经诱导已知涉及原肠胚形成过程中外胚层与背中胚层的相互作用，但几种研究认为，有能力的外胚层也可以通过与先前神经化组织的相互作用而神经化，这一过程被称为同源神经诱导。虽然同源神经诱导在神经组织的正常诱导中起着重要作用，但这一过程尚未受到组织重组和分子标记的详细研究。我们在移植和重组实验中研究了异爪蟾胚胎中神经诱导的同质性问题，使用两种神经抗原的表达来测定反应。当能够神经化的外胚层被移植到早期神经胚神经板附近的区域时，它就形成了神经组织，这是通过对神经细胞粘附分子N-CAM的抗体染色来检测的。移植到远离神经板的腹侧区域，不表达N-CAM，这表明神经化不是移植过程本身的结果。由于这种反应可能是由于外胚层与邻近的神经板组织或与下面的背外侧中胚层相互作用的结果，因此进行了重组实验以确定神经化信号的来源。单独与神经板组织结合培养的外胚层表达神经标记物，而与背外侧中胚层结合培养的外胚层不表达神经标记物。我们得出的结论是，神经组织可以同质诱导有能力的外胚层形成神经组织，并认为这种诱导是通过外胚层内的平面信号发生的，在正常发育中，这种机制可能涉及推定的神经外胚层内的相互作用或指定位于神经板附近的结构。
Neural induction is known to involve an interaction of ectoderm with dorsal mesoderm during gastrulation, but several kinds of studies have argued that competent ectoderm can also be neuralized via an interaction with previously neuralized tissue, a process termed homeogenetic neural induction. Although homeogenetic neural induction has been proposed to play an important role in the normal induction of neural tissue, this process has not been subjected to detailed study using tissue recombinants and molecular markers. We have examined the question of homeogenetic neural induction inXenopusembryos, both in transplant and recombinant experiments, using the expression of two neural antigens to assay the response. When ectoderm that is competent to be neuralized is transplanted to the region adjacent to the neural plate of early neurula embryos, it forms neural tissue, as assayed by staining with antibodies against the neural cell adhesion molecule, N-CAM. Transplants to the ventral region, far from the neural plate, do not express N-CAM, indicating that neuralization is not occurring as a result of the transplantation procedure itself. Because this response might be occurring as a result of interactions of ectoderm with either adjacent neural plate tissue, or with underlying dorsolateral mesoderm, recombinant experiments were performed to determine the source of the neuralizing signal. Ectoderm cultured in combination with neural plate tissue alone expresses neural markers, while ectoderm cultured in combination with dorsolateral mesoderm does not. We conclude that neural tissue can homeogenetically induce competent ectoderm to form neural tissue and argue that this induction occurs via planar signaling within the ectoderm, a mechanism that, in normal development, may be involved in interactions within presumptive neural ectoderm or in specifying structures that lie near the neural plate.