A PDZ-Binding Motif Controls Basolateral Targeting of Syndecan-1 Along the Biosynthetic Pathway in Polarized Epithelial Cells
A PDZ-Binding Motif Controls Basolateral Targeting of Syndecan-1 Along the Biosynthetic Pathway in Polarized Epithelial Cells
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DOI：
10.1111/j.1600-0854.2008.00805.x
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发表时间：
2008-11-01
期刊：
影响因子：
4.5
通讯作者：
Mellman, Ira
中科院分区：
文献类型：
--
作者：
Maday, Sandra;Anderson, Eric;Mellman, Ira
细胞表面蛋白聚糖syndecan-1对于正常上皮形态和功能至关重要。多配体蛋白聚糖-1选择性地定位于极化上皮细胞的基底外侧结构域，并与含有胞质PDZ（PSD-95，大碟，ZO-1）结构域的蛋白相互作用。在这里，我们表明，syndecan-1的极性是由其II型PDZ结合基序。PDZ结合基序内的突变导致多配体蛋白聚糖-1错误定位于顶端表面。然而，与先前的实施例相反，PDZ结合基序依赖性极性不是由基底外侧表面的保留决定的，而是由syndecan 1到达质膜之前的极化分选决定的。虽然没有四个已知的PDZ-结合的合作伙伴的syndecan-1出现控制基底外侧定位，我们的研究结果表明，PDZ-结合基序的syndecan-1的解码沿着的生物合成途径建立一个潜在的作用PDZ介导的相互作用，在极化分选。
The cell surface proteoglycan, syndecan-1, is essential for normal epithelial morphology and function. Syndecan-1 is selectively localized to the basolateral domain of polarized epithelial cells and interacts with cytosolic PDZ (PSD-95, discs large, ZO-1) domain-containing proteins. Here, we show that the polarity of syndecan-1 is determined by its type II PDZ-binding motif. Mutations within the PDZ-binding motif lead to the mislocalization of syndecan-1 to the apical surface. In contrast to previous examples, however, PDZ-binding motif-dependent polarity is not determined by retention at the basolateral surface but rather by polarized sorting prior to syndecan1's arrival at the plasma membrane. Although none of the four known PDZ-binding partners of syndecan-1 appears to control basolateral localization, our results show that the PDZ-binding motif of syndecan-1 is decoded along the biosynthetic pathway establishing a potential role for PDZ-mediated interactions in polarized sorting.