The interaction of two tethering factors, p115 and COG complex, is required for Golgi integrity
The interaction of two tethering factors, p115 and COG complex, is required for Golgi integrity
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DOI：
10.1111/j.1600-0854.2006.00530.x
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发表时间：
2007-03-01
期刊：
影响因子：
4.5
通讯作者：
Ikehara, Yukio
中科院分区：
文献类型：
--
作者：
Sohda, Miwa;Misumi, Yoshio;Ikehara, Yukio
囊泡束缚蛋白 p115 在内质网-高尔基体运输中发挥作用。我们探索了 p115 头结构域同源区 2 (HR2) 的功能，该结构域与酵母对应物 Uso1p 高度同源。通过在p115敲低（KD）细胞中表达p115突变体，我们发现HR2的缺失导致高尔基体的不规则组装，其由一簇微型堆积的高尔基体片段组成，并以微管依赖性方式聚集在微管组织中心周围。蛋白质相互作用分析表明，p115 HR2 与 Cog2 相互作用，Cog2 是保守寡聚高尔基体 (COG) 复合体的一个亚基，也是另一种假定的顺式高尔基体囊泡束缚因子。研究发现，p115 KD 或布雷菲德菌素 A 处理破坏高尔基体带，以及通过 p115 重新表达或药物洗脱恢复后，p115 和 Cog2 之间的相互作用对于高尔基体带重建至关重要。这种相互作用仅发生在间期细胞中，而不发生在有丝分裂细胞中。这些结果强烈表明，p115 通过与囊泡运输中顺式高尔基体上的 COG 复合体相互作用，在高尔基体的生物发生和维持中发挥重要作用。
The vesicle-tethering protein p115 functions in endoplasmic reticulum-Golgi trafficking. We explored the function of homologous region 2 (HR2) of the p115 head domain that is highly homologous with the yeast counterpart, Uso1p. By expression of p115 mutants in p115 knockdown (KD) cells, we found that deletion of HR2 caused an irregular assembly of the Golgi, which consisted of a cluster of mini-stacked Golgi fragments, and gathered around microtubule-organizing center in a microtubule-dependent manner. Protein interaction analyses revealed that p115 HR2 interacted with Cog2, a subunit of the conserved oligomeric Golgi (COG) complex that is known another putative cis-Golgi vesicle-tethering factor. The interaction between p115 and Cog2 was found to be essential for Golgi ribbon reformation after the disruption of the ribbon by p115 KD or brefeldin A treatment and recovery by re-expression of p115 or drug wash out, respectively. The interaction occurred only in interphase cells and not in mitotic cells. These results strongly suggested that p115 plays an important role in the biogenesis and maintenance of the Golgi by interacting with the COG complex on the cis-Golgi in vesicular trafficking.