scholarly journals [15] Transport from late endosomes to trans-golgi network in semiintact cell extracts

Author(s):  
Yukiko Goda ◽  
Thierry Soldati ◽  
Suzanne R. Pfeffer
1997 ◽  
Vol 8 (4) ◽  
pp. 577-582 ◽  
Author(s):  
Y Nakajima ◽  
S R Pfeffer

Mannose 6-phosphate receptors carry newly synthesized lysosomal hydrolases from the trans-Golgi network to endosomes, then return to the trans-Golgi network for another round of enzyme delivery. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, interferes with the delivery of newly synthesized lysosomal enzymes to lysosomes. We used two independent assays of mannose 6-phosphate receptor trafficking to determine the precise step that is blocked by wortmannin. Using an assay that monitors resialylation of desialylated cell surface 300-kDa mannose 6-phosphate receptors, we found that receptor endocytosis and transport to the trans-Golgi network were not inhibited by 2 microM wortmannin. In addition, this concentration of drug had no effect on the transport of the mannose 6-phosphate receptor from late endosomes to the trans-Golgi network using a system that reconstitutes this transport process in cell extracts. Under the same conditions, wortmannin significantly inhibited the generation of mature cathepsin D. In addition, the structurally unrelated phosphatidylinositol 3-kinase inhibitor, LY294002, was also without effect when added to in vitro endosome-trans-Golgi network transport reactions. These experiments demonstrate that the interruption in lysosomal enzyme targeting is most likely due to a wortmannin-sensitive process required for the export of these receptors from the trans-Golgi network, consistent with the established role of phosphatidylinositol 3-kinase in the equivalent transport process in Saccharomyces cerevisiae.


1999 ◽  
Vol 112 (6) ◽  
pp. 845-854 ◽  
Author(s):  
A.C. Valdez ◽  
J.P. Cabaniols ◽  
M.J. Brown ◽  
P.A. Roche

SNARE proteins are known to play a role in regulating intracellular protein transport between donor and target membranes. This docking and fusion process involves the interaction of specific vesicle-SNAREs (e.g. VAMP) with specific cognate target-SNAREs (e.g. syntaxin and SNAP-23). Using human SNAP-23 as the bait in a yeast two-hybrid screen of a human B-lymphocyte cDNA library, we have identified the 287-amino-acid SNARE protein syntaxin 11. Like other syntaxin family members, syntaxin 11 binds to the SNARE proteins VAMP and SNAP-23 in vitro and also exists in a complex with SNAP-23 in transfected HeLa cells and in native human B lymphocytes. Unlike other syntaxin family members, no obvious transmembrane domain is present in syntaxin 11. Nevertheless, syntaxin 11 is predominantly membrane-associated and colocalizes with the mannose 6-phosphate receptor on late endosomes and the trans-Golgi network. These data suggest that syntaxin 11 is a SNARE that acts to regulate protein transport between late endosomes and the trans-Golgi network in mammalian cells.


1999 ◽  
Vol 146 (2) ◽  
pp. 345-360 ◽  
Author(s):  
William G. Mallet ◽  
Frederick R. Maxfield

Furin and TGN38 are membrane proteins that cycle between the plasma membrane and the trans-Golgi network (TGN), each maintaining a predominant distribution in the TGN. We have used chimeric proteins with an extracellular Tac domain and the cytoplasmic domain of TGN38 or furin to study the trafficking of these proteins in endosomes. Previously, we demonstrated that the postendocytic trafficking of Tac-TGN38 to the TGN is via the endocytic recycling pathway (Ghosh, R.N., W.G. Mallet, T.T. Soe, T.E. McGraw, and F.R. Maxfield. 1998. J. Cell Biol. 142:923–936). Here we show that internalized Tac-furin is delivered to the TGN through late endosomes, bypassing the endocytic recycling compartment. The transport of Tac-furin from late endosomes to the TGN appears to proceed via an efficient, single-pass mechanism. Delivery of Tac-furin but not Tac-TGN38 to the TGN is blocked by nocodazole, and the two pathways are also differentially affected by wortmannin. These studies demonstrate the existence of two independent pathways for endosomal transport of proteins to the TGN from the plasma membrane.


1993 ◽  
Vol 12 (2) ◽  
pp. 677-682 ◽  
Author(s):  
D. Lombardi ◽  
T. Soldati ◽  
M.A. Riederer ◽  
Y. Goda ◽  
M. Zerial ◽  
...  

2021 ◽  
Vol 32 (1) ◽  
pp. 57-73
Author(s):  
Alexandria Brumfield ◽  
Natasha Chaudhary ◽  
Dorothee Molle ◽  
Jennifer Wen ◽  
Johannes Graumann ◽  
...  

Insulin signaling mobilizes glucose transporter 4 (GLUT4) from the trans-Golgi network (TGN) through the AKT-TBC1D4-RAB10 signaling module. GLUT4 localizes to a region of the TGN responsible for retention and release of ATP7A copper transporter and the sorting of lysosomal enzymes to late endosomes.


2000 ◽  
Vol 11 (2) ◽  
pp. 481-495 ◽  
Author(s):  
Paolo Nicoziani ◽  
Frederik Vilhardt ◽  
Alicia Llorente ◽  
Leila Hilout ◽  
Pierre J. Courtoy ◽  
...  

It is well established that dynamin is involved in clathrin-dependent endocytosis, but relatively little is known about possible intracellular functions of this GTPase. Using confocal imaging, we found that endogenous dynamin was associated with the plasma membrane, the trans-Golgi network, and a perinuclear cluster of cation-independent mannose 6-phosphate receptor (CI-MPR)–containing structures. By electron microscopy (EM), it was shown that these structures were late endosomes and that the endogenous dynamin was preferentially localized to tubulo-vesicular appendices on these late endosomes. Upon induction of the dominant-negative dynK44A mutant, confocal microscopy demonstrated a redistribution of the CI-MPR in mutant-expressing cells. Quantitative EM analysis of the ratio of CI-MPR to lysosome-associated membrane protein-1 in endosome profiles revealed a higher colocalization of the two markers in dynK44A-expressing cells than in control cells. Western blot analysis showed that dynK44A-expressing cells had an increased cellular procathepsin D content. Finally, EM revealed that in dynK44A-expressing cells, endosomal tubules containing CI-MPR were formed. These results are in contrast to recent reports that dynamin-2 is exclusively associated with endocytic structures at the plasma membrane. They suggest instead that endogenous dynamin also plays an important role in the molecular machinery behind the recycling of the CI-MPR from endosomes to the trans-Golgi network, and we propose that dynamin is required for the final scission of vesicles budding from endosome tubules.


2004 ◽  
Vol 15 (2) ◽  
pp. 721-733 ◽  
Author(s):  
Sharron X. Lin ◽  
William G. Mallet ◽  
Amy Y. Huang ◽  
Frederick R. Maxfield

Although the distribution of the cation-independent mannose 6-phosphate receptor (CI-MPR) has been well studied, its intracellular itinerary and trafficking kinetics remain uncertain. In this report, we describe the endocytic trafficking and steady-state localization of a chimeric form of the CI-MPR containing the ecto-domain of the bovine CI-MPR and the murine transmembrane and cytoplasmic domains expressed in a CHO cell line. Detailed confocal microscopy analysis revealed that internalized chimeric CI-MPR overlaps almost completely with the endogenous CI-MPR but only partially with individual markers for the trans-Golgi network or other endosomal compartments. After endocytosis, the chimeric receptor first enters sorting endosomes, and it then accumulates in the endocytic recycling compartment. A large fraction of the receptors return to the plasma membrane, but some are delivered to the trans-Golgi network and/or late endosomes. Over the course of an hour, the endocytosed receptors achieve their steady-state distribution. Importantly, the receptor does not start to colocalize with late endosomal markers until after it has passed through the endocytic recycling compartment. In CHO cells, only a small fraction of the receptor is ever detected in endosomes bearing substrates destined for lysosomes (kinetically defined late endosomes). These data demonstrate that CI-MPR takes a complex route that involves multiple sorting steps in both early and late endosomes.


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