Proteomic analysis of adaptor protein 1A coats selectively assembled on liposomes
Proteomic analysis of adaptor protein 1A coats selectively assembled on liposomes
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DOI：
10.1073/pnas.0511062103
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发表时间：
2006-02-28
影响因子：
11.1
通讯作者：
Hoflack, B
中科院分区：
文献类型：
--
作者：
Baust, T;Czupalla, C;Hoflack, B
外壳成分定位于特定的膜域，在那里它们对选定的跨膜蛋白进行分类。为了研究网格蛋白涂层如何在这些结构域上稳定并识别所涉及的蛋白质网络，我们结合了蛋白质组学筛选和体外基于脂质体的测定，这些测定概括了体内蛋白质分选的保真度。我们的研究鉴定了 AP-1A 包被脂质体上的大约 40 种蛋白质，结果表明 AP-1A 包被组装会触发 Rac1、其效应子、Wave/Scar 复合物以及 Rab11 和 RA14 的同时募集。这些不同机器的协调募集需要膜成分的镶嵌，其中包括 GTP 酶 ADP-核糖基化因子 1、选定跨膜蛋白中的分选信号和磷脂酰肌醇 4-磷酸。这些结果表明，同一膜结构域上存在的低亲和力结合位点的组合使用不仅可以解释选择性涂层组装，还可以协调组装肌动蛋白聚合和随后的膜融合所需的选定机器。
Coat components localize to specific membrane domains, where they sort selected transmembrane proteins. To study how clathrin coats are stabilized on such domains and to identify the protein networks involved, we combined proteomic screens and in vitro liposome-based assays that recapitulate the fidelity of protein sorting in vivo. Our study identifying approximate to 40 proteins on AP-1A-coated liposomes revealed that AP-1A coat assembly triggers the concomitant recruitment of Rac1, its effectors, and the Wave/Scar complex as well as that of Rab11 and RA14. The coordinated recruitment of these different machineries requires a mosaic of membrane components comprising the GTPase ADP-ribosylation factor 1, sorting signals in selected transmembrane proteins, and phosphatidylinositol 4-phosphate. These results demonstrate that the combinatorial use of low-affinity binding sites present on the same membrane domain accounts not only for a selective coat assembly but also for the coordinated assembly of selected machineries required for actin polymerization and subsequent membrane fusion.