The binding of plakoglobin to desmosomal cadherins: patterns of binding sites and topogenic potential.
The binding of plakoglobin to desmosomal cadherins: patterns of binding sites and topogenic potential.
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DOI：
10.1083/jcb.133.2.359
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发表时间：
1996-04
影响因子：
7.8
通讯作者：
Troyanovsky, SM
中科院分区：
文献类型：
--
作者：
Chitaev, NA;Leube, RE;Troyanovsky, RB;Eshkind, LG;Franke, WW;Troyanovsky, SM
血小板红蛋白是唯一出现在所有已知黏附连接的细胞质斑块中的蛋白质，并且已被证明通过与桥粒钙粘蛋白、桥粒蛋白（Dsg）和桥粒蛋白（Dsc）的相互作用，在桥粒锚定中等大小纤维丝（if）的形成和维持中起着至关重要的作用。现在在活细胞和体外结合试验中直接显示了血小板红蛋白的拓扑重要性。我们发现，在转染的人a -431癌细胞中，一种将形成囊泡的跨膜糖蛋白synaptophysin与完整的人血小板红蛋白序列结合在一起的嵌合蛋白被分类成小囊泡，其中许多与桥粒斑块及其附着的IFs相关。免疫沉淀实验进一步揭示了这些囊泡的嵌合含血小板红蛋白的跨膜分子与Dsg和Dsc紧密结合，但不与内源性血小板红蛋白结合，从而表明血小板红蛋白与桥粒体钙粘蛋白的结合不需要其可溶状态，并且足够强，可以将囊泡等大型结构附着在桥粒上。为了确定血小板红蛋白与桥粒钙粘蛋白相互作用的结合域和机制，我们在体外开发了直接结合试验，在大肠杆菌中通过重组DNA技术产生血小板红蛋白或其部分，将其暴露于含有几种钙粘蛋白“C-结构域”的分子中。这些实验表明，血小板红蛋白与Dsg的c结构域联系最紧密，与Dsc的联系程度较低，与e -钙粘蛋白的c结构域联系较弱。含有不同数量的所谓臂重复序列的三个单独的血小板红蛋白片段，与整个分子的强度相当，表现出与桥粒钙粘蛋白的明显结合。将血小板红蛋白片段在体外与体内的结合模式进行了比较。矛盾的是，在体外，一些内部的血小板红蛋白片段与e -钙粘蛋白的c结构域的结合甚至比整个分子更好，这表明天然血小板红蛋白中存在干扰该蛋白与其各种钙粘蛋白伴侣相互作用的元素。
Plakoglobin is the only protein that occurs in the cytoplasmic plaques of all known adhering junctions and has been shown to be crucially involved in the formation and maintenance of desmosomes anchoring intermediate-sized filaments (IFs) by its interaction with the desmosomal cadherins, desmoglein (Dsg), and desmocollin (Dsc). This topogenic importance of plakoglobin is now directly shown in living cells as well as in binding assays in vitro. We show that, in transfected human A-431 carcinoma cells, a chimeric protein combining the vesicle-forming transmembrane glycoprotein synaptophysin, with the complete human plakoglobin sequence, is sorted to small vesicles many of which associate with desmosomal plaques and their attached IFs. Immunoprecipitation experiments have further revealed that the chimeric plakoglobin-containing transmembrane molecules of these vesicles are tightly bound to Dsg and Dsc but not to endogenous plakoglobin, thus demonstrating that the binding of plakoglobin to desmosomal cadherins does not require its soluble state and is strong enough to attach large structures such as vesicles to desmosomes. To identify the binding domains and the mechanisms involved in the interaction of plakoglobin with desmosomal cadherins, we have developed direct binding assays in vitro in which plakoglobin or parts thereof, produced by recombinant DNA technology in E. coli, are exposed to molecules containing the "C- domains" of several cadherins. These assays have shown that plakoglobin associates most tightly with the C-domain of Dsg, to a lesser degree with that of Dsc and only weakly with the C-domain of E-cadherin. Three separate segments of plakoglobin containing various numbers of the so- called arm repeats exhibit distinct binding to the desmosomal cadherins comparable in strength to that of the entire molecule. The binding pattern of plakoglobin segments in vitro is compared with that in vivo. Paradoxically, in vitro some internal plakoglobin fragments bind even better to the C-domain of E-cadherin than the entire molecule, indicating that elements exist in native plakoglobin that interfere with the interaction of this protein with its various cadherin partners.
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DOI：
10.1083/jcb.118.3.671
发表时间：
1992-08
期刊：
The Journal of cell biology
影响因子：
--
作者：
Knudsen KA;Wheelock MJ
通讯作者：
Wheelock MJ
DOI：
10.1007/bf00712737
发表时间：
1987-01-01
期刊：
VIRCHOWS ARCHIV A-PATHOLOGICAL ANATOMY AND HISTOPATHOLOGY
影响因子：
--
作者：
FRANKE, WW;WINTER, S;STAHLI, C
通讯作者：
STAHLI, C
DOI：
10.1111/j.1432-1033.1987.tb13543.x
发表时间：
1987-08-03
期刊：
EUROPEAN JOURNAL OF BIOCHEMISTRY
影响因子：
--
作者：
KAPPRELL, HP;COWIN, P;FRANKE, WW
通讯作者：
FRANKE, WW
DOI：
10.1101/sqb.1992.057.01.070
发表时间：
1992-01-01
期刊：
COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY
影响因子：
--
作者：
FRANKE, WW;TROYANOVSKY, SM;LEUBE, RE
通讯作者：
LEUBE, RE
DOI：
10.1083/jcb.125.6.1327
发表时间：
1994-06
期刊：
The Journal of cell biology
影响因子：
--
作者：
Hinck L;Näthke IS;Papkoff J;Nelson WJ
通讯作者：
Nelson WJ