Metameric pattern of intervertebral disc/vertebral body is generated independently of Mesp2/Ripply-mediated rostro-caudal patterning of somites in the mouse embryo.
Metameric pattern of intervertebral disc/vertebral body is generated independently of Mesp2/Ripply-mediated rostro-caudal patterning of somites in the mouse embryo.
复制标题
椎间盘/椎体的同色异谱模式的产生独立于 Mesp2/Ripply 介导的小鼠胚胎体节的头尾模式。
DOI：
10.1016/j.ydbio.2013.05.020
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Kanno J.
中科院分区：
文献类型：
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作者：
Takahashi Y;Yasuhiko Y;Takahashi J;Takada S;Johnson RL;Saga Y;Kanno J.
脊椎骨是由体节的菌核发育而来的。椎体的形成涉及一个被称为再分割的过程，通过这个过程，一个菌核的尾侧半部分与下一个菌核的嘴半部分结合。为了阐明再分裂与体节嘴-尾模式的关系，我们使用了Uncx4.1-lacZ转基因来表征再分裂过程。我们的观察表明，在胸椎和腰椎中，表达Uncx4.1的尾部硬化症形成了椎间盘(IVD)和椎体吻部(Vb)。在颈椎中，表达Uncx4.1的尾端硬化节似乎与IVD以及Vb的尾端和吻端有关。这一发现表明，吻尾基因表达边界并不一定与再分段边界重合。这一结论得到了Mesp2KO和Ripply1/2双KO胚胎的分析，它们分别缺乏吻部和尾部特性。在Mesp2KO胚胎中没有观察到再分离，但IVD和整个VB都是由尾化的菌核形成的。对包括Pax1在内的IVD标记基因在野生型、Mesp2 KO和Ripply1/2 DKO胚胎中的表达分析也支持这样的观点，即IVD/VB的异构体模式是独立于Mesp2/Ripply介导的体节的喙-尾模式而产生的。然而，在腰部，IVD的分化似乎受到尾部特性的刺激，而受到吻部特性的抑制。因此，我们认为体节的吻尾模式不是IVD和VB异构体模式形成的先决条件，而是刺激核心体尾部的IVD分化所必需的。
The vertebrae are derived from the sclerotome of somites. Formation of the vertebral body involves a process called resegmentation, by which the caudal half of a sclerotome is combined with the rostral half of the next sclerotome. To elucidate the relationship between resegmentation and rostro-caudal patterning of somite, we used the Uncx4.1-LacZ transgene to characterize the resegmentation process. Our observations suggested that in the thoracic and lumbar vertebrae, the Uncx4.1-expressing caudal sclerotome gave rise to the intervertebral disc (IVD) and rostral portion of the vertebral body (VB). In the cervical vertebrae, the Uncx4.1-expressing caudal sclerotome appeared to contribute to the IVD and both caudal and rostral ends of the VB. This finding suggests that the rostro-caudal gene expression boundary does not necessarily coincide with the resegmentation boundary. This conclusion was supported by analyses of Mesp2 KO and Ripply1/2 double KO embryos lacking rostral and caudal properties, respectively. Resegmentation was not observed in Mesp2 KO embryos, but both the IVD and whole VB were formed from the caudalized sclerotome. Expression analysis of IVD marker genes including Pax1 in the wild-type, Mesp2 KO, and Ripply1/2 DKO embryos also supported the idea that a metameric pattern of IVD/VB is generated independently of Mesp2/Ripply-mediated rostro-caudal patterning of somite. However, in the lumbar region, IVD differentiation appeared to be stimulated by the caudal property and suppressed by the rostral property. Therefore, we propose that rostro-caudal patterning of somites is not a prerequisite for metameric patterning of the IVD and VB, but instead required to stimulate IVD differentiation in the caudal half of the sclerotome.