Fourriere Lou, Divoux Severine, Roceri Mila, Perez Franck, Boncompain Gaelle
Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France UPMC, 75005 Paris, France.
Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France.
J Cell Sci. 2016 Sep 1;129(17):3238-50. doi: 10.1242/jcs.188870. Epub 2016 Jul 13.
The Golgi complex is responsible for processing and sorting of secretory cargos. Microtubules are known to accelerate the transport of proteins from the endoplasmic reticulum (ER) to the Golgi complex and from the Golgi to the plasma membrane. However, whether post-Golgi transport strictly requires microtubules is still unclear. Using the retention using selective hooks (RUSH) system to synchronize the trafficking of cargos, we show that anterograde transport of tumor necrosis factor (TNF) is strongly reduced without microtubules. We show that two populations of Golgi elements co-exist in these cells. A centrally located and giantin-positive Golgi complex that sustains trafficking, and newly formed peripheral Golgi mini-stacks that accumulate cargos in cells without microtubules. Using a genome-edited GFP-giantin cell line, we observe that the trafficking-competent Golgi population corresponds to the pre-existing population that was present before removal of microtubules. All Golgi elements support trafficking after long-term depletion of microtubules and after relocation of Golgi proteins to the ER after treatment with Brefeldin A. Our results demonstrate that functional maturation of Golgi elements is needed to ensure post-Golgi trafficking, and that microtubule-driven post-Golgi transport is not strictly required.
高尔基体负责分泌货物的加工和分选。已知微管可加速蛋白质从内质网（ER）到高尔基体以及从高尔基体到质膜的运输。然而，高尔基体后运输是否严格需要微管仍不清楚。利用选择性钩留（RUSH）系统同步货物运输，我们发现没有微管时肿瘤坏死因子（TNF）的顺行运输会大幅减少。我们发现这些细胞中存在两种高尔基体元件群体。一种是位于中央且巨蛋白阳性的高尔基体复合体，维持运输；另一种是新形成的外周高尔基体小堆栈，在没有微管的细胞中积累货物。利用基因编辑的绿色荧光蛋白-巨蛋白细胞系，我们观察到具有运输能力的高尔基体群体对应于去除微管之前就已存在的原有群体。在微管长期缺失后以及用布雷菲德菌素A处理后高尔基体蛋白重新定位到内质网后，所有高尔基体元件都支持运输。我们的结果表明，高尔基体元件的功能成熟是确保高尔基体后运输所必需的，并且微管驱动的高尔基体后运输并非严格必需。
