YIPF5 and YIF1A recycle between the ER and the Golgi apparatus and are involved in the maintenance of the Golgi structure.
YIPF5 and YIF1A recycle between the ER and the Golgi apparatus and are involved in the maintenance of the Golgi structure.
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DOI：
10.1016/j.yexcr.2008.07.023
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发表时间：
2008-11
影响因子：
3.7
通讯作者：
Y. Yoshida;Kurumi Suzuki;A. Yamamoto;N. Sakai;Misako Bando;Kouji Tanimoto;Y. Yamaguchi;Tomoaki Sakaguchi;H. Akhter;G. Fujii;S. Yoshimura;S. Ogata;M. Sohda;Y. Misumi;N. Nakamura
中科院分区：
文献类型：
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作者：
Y. Yoshida;Kurumi Suzuki;A. Yamamoto;N. Sakai;Misako Bando;Kouji Tanimoto;Y. Yamaguchi;Tomoaki Sakaguchi;H. Akhter;G. Fujii;S. Yoshimura;S. Ogata;M. Sohda;Y. Misumi;N. Nakamura
Yif1p /Yif1p家族蛋白是定位于高尔基体和内质网的五跨跨膜蛋白。在人类中有9个家族成员，YIPF5和YIF1A分别是出芽酵母Yip1p和Yif1p的人类同源物。我们培养了针对YIPF5和YIF1A的抗血清，并检测了内源性蛋白在HeLa细胞中的定位。免疫荧光、免疫电镜和亚细胞分离分析表明，YIPF5和YIF1A不仅局限于内质网出口位点，而且在稳定状态下也定位于内质网-高尔基体中间区（ERGIC）和部分顺式高尔基体。在brefeldin A处理后，YIPF5和YIF1A与ERGIC53一起留在细胞质点状结构中，在alf4处理后积聚在ERGIC和顺式高尔基体中，当Sar1（H79G）抑制ER向高尔基体的运输时积聚在内质网中。这些结果支持了YIPF5和YIF1A在ERGIC和顺式高尔基体中的定位，并强烈提示它们在内质网和高尔基体之间循环。蓝色原生PAGE和共免疫沉淀分析表明，YIPF5和YIF1A形成了三种不同大小的稳定复合物。有趣的是，YIPF5或YIF1A的敲低导致高尔基体的部分解体，这表明YIPF5和YIF1A参与了高尔基体结构的维持。
Yip1p/Yif1p family proteins are five-span transmembrane proteins localized in the Golgi apparatus and the ER. There are nine family members in humans, and YIPF5 and YIF1A are the human orthologs of budding yeast Yip1p and Yif1p, respectively. We raised antisera against YIPF5 and YIF1A and examined the localization of endogenous proteins in HeLa cells. Immunofluorescence, immunoelectron microscopy and subcellular fractionation analysis suggested that YIPF5 and YIF1A are not restricted to ER exit sites but also localized in the ER–Golgi intermediate compartment (ERGIC) and some in the cis-Golgi at steady state. Along with ERGIC53, YIPF5 and YIF1A remained in the cytoplasmic punctate structures after brefeldin A treatment, accumulated in the ERGIC and the cis-Golgi after treatment with AlF4-and accumulated in the ER when ER to Golgi transport was inhibited by Sar1(H79G). These results supported the localization of YIPF5 and YIF1A in the ERGIC and the cis-Golgi, and strongly suggested that they are recycling between the ER and the Golgi apparatus. Analysis by blue native PAGE and co-immunoprecipitation showed that YIPF5 and YIF1A form stable complexes of three different sizes. Interestingly, the knockdown of YIPF5 or YIF1A caused partial disassembly of the Golgi apparatus suggesting that YIPF5 and YIF1A are involved in the maintenance of the Golgi structure.