The Intracellular Interactome of Tetraspanin-enriched Microdomains Reveals Their Function as Sorting Machineries toward Exosomes
The Intracellular Interactome of Tetraspanin-enriched Microdomains Reveals Their Function as Sorting Machineries toward Exosomes
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DOI：
10.1074/jbc.m112.445304
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发表时间：
2013-04-26
影响因子：
4.8
通讯作者：
Yanez-Mo, Maria
中科院分区：
文献类型：
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作者：
Perez-Hernandez, Daniel;Gutierrez-Vazquez, Cristina;Yanez-Mo, Maria
细胞外囊泡作为细胞间通讯的一种有效机制正在兴起，因为它们可以在细胞之间系统地交换遗传和蛋白质物质。四跨膜蛋白分子通常用作细胞外囊泡的蛋白质标记物，尽管它们在未探索的货物选择进入外泌体的机制中的作用尚未得到解决。为此，我们已经通过高通量质谱法表征了人淋巴母细胞及其衍生的外泌体中的细胞内四跨膜蛋白富集的微结构域（TEM）相互作用体，揭示了相互作用网络的清晰模式。与TEM受体胞质区域相互作用的蛋白质呈现出相当程度的重叠，尽管检测到一些高度特异性的CD81四跨膜蛋白配体，如Rac GT3。定量蛋白质组学表明，TEM配体占外泌体蛋白质组的很大比例，并且CD81相关分子（包括Rac）的选择性库不能正确地路由到来自CD81缺陷动物的细胞中的外泌体。我们的数据提供的证据表明，插入TEM可能是必要的蛋白质纳入外泌体结构。
Extracellular vesicles are emerging as a potent mechanism of intercellular communication because they can systemically exchange genetic and protein material between cells. Tetraspanin molecules are commonly used as protein markers of extracellular vesicles, although their role in the unexplored mechanisms of cargo selection into exosomes has not been addressed. For that purpose, we have characterized the intracellular tetraspanin-enriched microdomain (TEM) interactome by high throughput mass spectrometry, in both human lymphoblasts and their derived exosomes, revealing a clear pattern of interaction networks. Proteins interacting with TEM receptors cytoplasmic regions presented a considerable degree of overlap, although some highly specific CD81 tetraspanin ligands, such as Rac GTPase, were detected. Quantitative proteomics showed that TEM ligands account for a great proportion of the exosome proteome and that a selective repertoire of CD81-associated molecules, including Rac, is not correctly routed to exosomes in cells from CD81-deficient animals. Our data provide evidence that insertion into TEM may be necessary for protein inclusion into the exosome structure.