Expression patterns of Sema3A in developing amniote limbs: With reference to the diversification of peripheral nerve innervation.
Expression patterns of Sema3A in developing amniote limbs: With reference to the diversification of peripheral nerve innervation.
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Sema3A 在羊膜四肢发育中的表达模式：参考周围神经支配的多样化。
DOI：
10.1111/dgd.12364
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Murakami Y.
中科院分区：
文献类型：
--
作者：
Noguchi K;Ishikawa R;Kawaguchi M;Miyoshi K;Kawasaki T;Hirata T;Fukui M; Kuratani S;Tanaka M;Murakami Y.
在四足动物的祖先中获得了成对肢体，并且由于对陆地环境的适应辐射，羊膜动物的四肢形态高度多样化。这些形态变化可能是由于骨骼或肌肉系统发育程序的改变而引起的。为了完成肢体改造，改变神经元框架也很重要，因为肢体的功能依赖于涉及协调运动的神经回路。先前的研究表明，3类信号蛋白（Sema3信号蛋白）作为排斥性轴突引导信号在小鼠周围神经的形成中起着至关重要的作用。在此，我们研究了sema3aorthologues在发育中的羊膜动物胚胎中的表达模式，包括小鼠、小鸡、软壳龟和豹纹壁虎。在所有研究的动物中，sema3a转录因子在发育中的肢体原基的有限间充质部分表达，并且发育中的脊神经似乎延伸到sema3a阴性区域。这些结果表明，依赖aSema3A的引导系统在羊膜肢体神经元回路形成中起关键作用。我们还发现sema3与软骨前体细胞的分布部分重叠。基于这些结果，我们提出了一个轴突引导和骨骼形成由ysema3a连接的模型；这种机制可能是肢体分化过程中功能性神经元重排的基础。
Paired limbs were acquired in the ancestor of tetrapods and their morphology has been highly diversified in amniotes in relation to the adaptive radiation to the terrestrial environment. These morphological changes may have been induced by modification of the developmental program of the skeletal or muscular system. To complete limb modification, it is also important to change the neuronal framework, because the functions of the limbs rely on neural circuits that involve coordinated movement. Previous studies have shown that class 3 semaphorins (Sema3 semaphorins), which act as repulsive axonal guidance cues, play a crucial role in the formation of the peripheral nerves in mice. Here, we studied the expression pattern ofSema3Aorthologues in embryos of developing amniotes, including mouse, chick, soft‐shelled turtle, and ocelot gecko.Sema3Atranscripts were expressed in restricted mesenchymal parts of the developing limb primordium in all animals studied, and developing spinal nerves appeared to extend throughSema3A‐negative regions. These results suggest that aSema3A‐dependent guidance system plays a key role in neuronal circuit formation in amniote limbs. We also found thatSema3Apartially overlapped with the distribution of cartilage precursor cells. Based on these results, we propose a model in which axon guidance and skeletogenesis are linked bySema3A; such mechanisms may underlie functional neuron rearrangement during limb diversification.