title: Microtubule-independent secretion requires functional maturation of Golgi elements.
abstract: 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.
authors.affiliation: Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France UPMC, 75005 Paris, France.
authors.forename: Lou
authors.initials: L
authors.lastname: Fourriere
authors.affiliation: Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France.
authors.forename: Severine
authors.initials: S
authors.lastname: Divoux
authors.affiliation: Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France.
authors.forename: Mila
authors.initials: M
authors.lastname: Roceri
authors.affiliation: Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France franck.perez@curie.fr.
authors.forename: Franck
authors.identifier: 0000-0002-9129-9401
authors.initials: F
authors.lastname: Perez
authors.affiliation: Institut Curie, Centre de Recherche, PSL research University, 75005 Paris, France CNRS UMR144, 75005 Paris, France.
authors.forename: Gaelle
authors.initials: G
authors.lastname: Boncompain
mesh_terms: D001692:Biological Transport; D004705:Endocytosis; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008870:Microtubules / Q000378:metabolism*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D014409:Tumor Necrosis Factor-alpha
keywords: Golgi; Intracellular trafficking; Microtubules