COPII-cargo interactions direct protein sorting into ER-derived transport vesicles
COPII-cargo interactions direct protein sorting into ER-derived transport vesicles
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DOI：
10.1038/34438
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发表时间：
1998-01-08
期刊：
影响因子：
64.8
通讯作者：
Schekman, R
中科院分区：
文献类型：
--
作者：
Kuehn, MJ;Herrmann, JM;Schekman, R
包被有外壳蛋白复合物II（COPII）的囊泡选择性地将分子（货物）和囊泡融合蛋白从内质网（ER）转运至高尔基复合物（1-3）。我们已经研究了外壳蛋白在货物选择和招募中的作用。我们分离出了在Sar 1和Sec 23/24（COPII组分的一个子集）和GTP或GMP-PNP存在下形成的复合物中用于从ER转运的膜和可溶性货物蛋白。在COPII复合物中还发现了vSNARE家族的囊泡融合蛋白和Emp 24（推定的货物载体家族的成员（4））。包含氨基酸通透酶分子进入复合物取决于存在的Shr 3，蛋白质所需的通透酶离开ER 3，5。常驻ER蛋白Sec 61，BiP（Kar 2）和Shr 3不包括在复合物中，表明COPII组分特异性结合囊泡货物。还从COPII囊泡中分离COPII-货物复合物和推定的货物衔接子-货物复合物。我们的研究结果表明，货物包装信号和可溶性货物衔接子识别的招聘复合物，包括Sar 1-GTP和Sec 23/24。
Vesicles coated with coat protein complex II (COPII) selectively transport molecules (cargo) and vesicle fusion proteins from the endoplasmic reticulum (ER) to the Golgi complex(1-3). We have investigated the role of coat proteins in cargo selection and recruitment. We isolated integral membrane and soluble cargo proteins destined for transport from the ER in complexes formed in the presence of Sar1 and Sec23/24, a subset of the COPII components, and GTP or GMP-PNP. Vesicle fusion proteins of the vSNARE family and Emp24, a member of a putative cargo carrier family(4), were also found in COPII complexes. The inclusion of amino-acid permease molecules into the complex depended on the presence of Shr3, a protein required for the permease to leave the ER3,5. Resident ER proteins Sec61, BiP (Kar2) and Shr3 were not included in the complexes, indicating that the COPII components bound specifically to vesicle cargo. COPII-cargo complexes and putative cargo adaptor-cargo complexes were also isolated from COPII vesicles. Our results indicate that cargo packaging signals and soluble cargo adaptors are recognized by a recruitment complex comprising Sar1-GTP and Sec23/24.