Expression of multiple cadherins and catenins in the chick optic tectum
Expression of multiple cadherins and catenins in the chick optic tectum
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DOI：
10.1006/mcne.1998.0718
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发表时间：
1998-11-01
影响因子：
3.5
通讯作者：
Sanes, JR
中科院分区：
文献类型：
--
作者：
Miskevich, F;Zhu, Y;Sanes, JR
钙粘蛋白是一大类亲同性细胞粘附分子，参与神经发育的许多方面。研究最充分的神经钙粘蛋白n -钙粘蛋白集中在小鸡视神经顶盖视网膜轴突形成的突触上，并且是视网膜轴突在其靶（视网膜受体）层中的树突化所必需的。类似地，其他钙粘蛋白也可能介导其他顶片状的树突形成或突触发生。在这里，我们考虑哪些钙粘蛋白在顶盖中表达，哪些细胞表达它们，以及它们的表达是如何被调节的。首先，以N-cadherin为模型，我们发现突触输入调节cadherin基因表达和cadherin蛋白的亚细胞分布。其次，我们证明了N-、R-和t -钙粘蛋白在视网膜顶突触发生过程中以不同的层流模式表达，并且N-和R-在不重叠的突触亚群中富集。第三，我们发现在突触形成期间，超过20个钙粘蛋白超家族基因在顶盖中表达，其中许多基因在有限的细胞群中表达。最后，我们报道了-连环蛋白和-连环蛋白（血小板红蛋白），钙粘蛋白信号传递所需的细胞质蛋白，在突触富集并与n -钙粘蛋白相关。然而，β -连环蛋白和γ -连环蛋白分布和调控不同，形成互斥复合物。这一结果表明，基于钙粘蛋白的特异性涉及多种钙粘蛋白依赖的信号通路以及多种钙粘蛋白。
Cadherins form a large family of homophilic cell adhesion molecules that are involved in numerous aspects of neural development. The best-studied neural cadherin, N-cadherin, is concentrated at synapses made by retinal axons in the chick optic tectum and is required for the arborization of retinal axons in their target (retinorecipient) laminae. By analogy, other cadherins might mediate arborization or synaptogenesis in other tectal laminae. Here we consider which cadherins are expressed in tectum, which cells express them, and how their expression is regulated. First, using N-cadherin as a model, we show that synaptic input regulates both cadherin gene expression and the subcellular distribution of cadherin protein. Second, we demonstrate that N-, R-, and T-cadherin are each expressed in distinct laminar patterns during retinotectal synaptogenesis and that N- and R- are enriched in nonoverlapping synaptic subsets. Third, we show that over 20 cadherin superfamily genes are expressed in the tectum during the time that synapses are forming and that many of them are expressed in restricted groups of cells. Finally, we report that both beta-catenin and gamma-catenin (plakoglobin), cytoplasmic proteins required for cadherin signaling, are enriched at synapses and associated with N-cadherin. However, beta- and gamma-catenins are differentially distributed and regulated, and form mutually exclusive complexes. This result suggests that cadherin-based specificity involves multiple cadherin-dependent signaling pathways as well as multiple cadherins.