Patterning of proneuronal and inter-proneuronal domains by hairy- and enhancer of split-related genes in zebraf ish neuroectoderm
Patterning of proneuronal and inter-proneuronal domains by hairy- and enhancer of split-related genes in zebraf ish neuroectoderm
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DOI：
10.1242/dev.01710
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发表时间：
2005-03-01
期刊：
影响因子：
4.6
通讯作者：
Hibi, M
中科院分区：
文献类型：
--
作者：
Bae, YK;Shimizu, T;Hibi, M
在硬骨鱼和两栖动物中，产生初级-运动神经元、初级-间神经元和Rohon-Beard （RB）神经元的前神经元域在神经发生开始时就在背外胚层沿前后轴形成了三条纵向条纹。proneuronal。结构域以表达基本螺旋-环-螺旋（bHLH）前膜基因为预示，由不表达前膜基因的结构域（前膜间结构域）分隔。关于这些结构域的形成是如何在空间上受到调控的，我们知之甚少。我们发现斑马鱼的分裂相关（Her）基因her3和her9的毛状和增强子在前神经元间区域表达，并且是其形成所必需的。her3和her9的表达不受Notch信号的调控，而是受位置信号的控制，其中涉及Bmp信号。反义morpholino寡核苷酸抑制Her3或Her9导致部分前神经元间区域的前基因异位表达。Her3和Her9的联合抑制诱导神经板中前神经元和神经元基因的普遍表达，并消除前神经元间结构域的形成。此外，抑制Her3/Her9和Notch信号通路导致神经板中普遍且均匀的前神经和神经元基因表达，这表明Her3/Her9和Notch信号通路在神经发生中具有不同的作用。这些数据表明，her3和her9作为前模式基因，将后神经外胚层的位置背腹侧极性信息与神经发生的空间调节联系起来。
In teleosts and amphibians, the proneuronal domains, which give rise to primary-motor, primary-inter and Rohon-Beard (RB) neurons, are established at the beginning of neurogenesis as three longitudinal stripes along the anteroposterior axis in the dorsal ectoderm. The proneuronal. domains are prefigured by the expression of basic helix-loop-helix (bHLH) proneural genes, and separated by domains (inter-proneuronal domains) that do not express the proneural genes. Little is known about how the formation of these domains is spatially regulated. We have found that the zebrafish hairy- and enhancer of split-related (Her) genes her3 and her9 are expressed in the inter-proneuronal domains, and are required for their formation. her3 and her9 expression was not regulated by Notch signaling, but rather controlled by positional cues, in which Bmp signaling is involved. Inhibition of Her3 or Her9 by antisense morpholino oligonucleotides led to ectopic expression of the proneural genes in part of the inter-proneuronal domains. Combined inhibition of Her3 and Her9 induced ubiquitous expression of proneural and neuronal genes in the neural plate, and abolished the formation of the inter-proneuronal domains. Furthermore, inhibition of Her3/Her9 and Notch signaling led to ubiquitous and homogeneous expression of proneural and neuronal genes in the neural plate, revealing that Her3/Her9 and Notch signaling have distinct roles in neurogenesis. These data indicate that her3 and her9 function as prepattern genes that link the positional dorsoventral polarity information in the posterior neuroectoderm to the spatial regulation of neurogenesis.