Xenopus Pax-6 and retinal development.
Xenopus Pax-6 and retinal development.
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DOI：
10.1002/(sici)1097-4695(199701)32:1
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
N. Hirsch;W. Harris
中科院分区：
文献类型：
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作者：
N. Hirsch;W. Harris
我们已经在非洲爪蟾中克隆了Pax-6的同源物。其推导的氨基酸序列与其他脊椎动物中的Pax-6同源物具有95%的总体同源性。它在发育的早期在注定形成眼睛和前脑、后脑和脊髓部分的细胞中表达。它在眼睛里有两个表达阶段。在早期阶段，从12.5期到33/34期，爪蟾Pax-6在整个发育中的视网膜中表达。在晚期，在33/34期之后，它被排除在视网膜外半部的成熟细胞和睫状边缘区的细胞之外，仅保留在无长突细胞和神经节细胞中。Pax-6在发育早期的错误表达导致眼轴缺陷，但没有观察到特定的眼表型。在后期阶段视网膜中的靶向错误表达不会导致任何显著的偏向于形成无长突细胞或神经节细胞或远离光感受器。前神经基因NeuroD的异位表达改变了Pax-6的模式，大大减少了其在眼区的表达，随后减少或消除了眼睛本身。我们的研究结果表明，Pax-6的表达似乎是必要的，但不是足够的，在非洲爪蟾眼睛的形成。
We have cloned a homolog of Pax-6 in Xenopus laevis. Its deduced amino acid sequence has a 95% overall identity with Pax-6 homologs in other vertebrates. It is expressed early in development in cells fated to form the eye and parts of the forebrain, hindbrain, and spinal cord. It has two phases of expression in the eye. In the early phase, from stage 12.5 to stage 33/34, Xenopus Pax-6 is expressed throughout the developing retina. In the late phase, after stage 33/34, it is excluded from mature cells in the outer half of the retina and from cells in the ciliary marginal zone, remaining only in amacrine and ganglion cells. Misexpression of Pax-6 early in development results in axial defects, but no specific eye phenotype is observed. Targeted misexpression in the retina at later stages does not result in any significant bias toward formation of amacrine or ganglion cells or away from photoreceptors. Ectopic expression of the proneural gene NeuroD alters the pattern of Pax-6, substantially reducing its expression in the eye field and later reducing or eliminating the eye itself. Our results show that Pax-6 expression appears to be necessary, but not sufficient, for eye formation in Xenopus.