Tetraspanin protein CD9 is a novel paranodal component regulating paranodal junctional formation
Tetraspanin protein CD9 is a novel paranodal component regulating paranodal junctional formation
复制标题
DOI：
10.1523/jneurosci.1484-03.2004
复制
发表时间：
2004-01-07
影响因子：
5.3
通讯作者：
Baba, H
中科院分区：
文献类型：
--
作者：
Ishibashi, T;Ding, L;Baba, H
轴神经胶质节点旁连接对于朗飞结周围离子通道的正确定位至关重要。该连接的完整性对于神经传导很重要。尽管最近的研究在理解节旁连接的分子组成方面取得了重大进展，但尚不清楚这些膜成分如何分布到适当的位点并相互作用。在这里，我们显示 CD9（四跨膜蛋白家族的成员）存在于旁节点。随着髓鞘形成的进行，CD9 集中在旁节中，但在脑苷脂磺基转移酶缺陷小鼠中，CD9 簇变得弥散，这与旁节的破坏有关。免疫组织化学和蛋白质印迹分析表明CD9主要分布在PNS中。突变小鼠中 CD9 的消融破坏了旁节处的连接附着，并改变了节旁成分接触素相关蛋白（也称为 Paranodin）和神经成束蛋白 155，尽管这种异常的频率在个体和个体轴突之间存在差异，甚至在同一只小鼠中也是如此。电子显微照片表明，PNS 中致密的髓鞘也受到影响。因此，CD9 是一种对于结旁连接形成很重要的髓磷脂蛋白。 CD9 还在 PNS 中致密髓磷脂的形成中发挥作用。
The axoglial paranodal junction is essential for the proper localization of ion channels around the node of Ranvier. The integrity of this junction is important for nerve conduction. Although recent studies have made significant progress in understanding the molecular composition of the paranodal junction, it is not known how these membrane components are distributed to the appropriate sites and interact with each other. Here we show that CD9, a member of the tetraspanin family, is present at the paranode. CD9 is concentrated in the paranode as myelination proceeds, but CD9 clusters become diffuse, associated with disruption of the paranode, in cerebroside sulfotransferase-deficient mice. Immunohistochemical and Western blot analysis showed that CD9 is distributed predominantly in the PNS. Ablation of CD9 in mutant mice disrupts junctional attachment at the paranode and alters the paranodal components contactin-associated protein ( also known as Paranodin) and neurofascin 155, although the frequency of such abnormalities varies among individuals and individual axons even in the same mouse. Electron micrographs demonstrated that compact myelin sheaths were also affected in the PNS. Therefore, CD9 is a myelin protein important for the formation of paranodal junctions. CD9 also plays a role in the formation of compact myelin in the PNS.