English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Pre- and post-Golgi translocation of glucosylceramide in glycosphingolipid synthesis

MPS-Authors
/persons/resource/persons219762

Vieira,  Otilia V.
Max Planck Institute of Molecular Cell Biology and Genetics, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Halter, D., Neumann, S., Dijk, S. M. v., Wolthoorn, J., Mazière, A. M. d., Vieira, O. V., et al. (2007). Pre- and post-Golgi translocation of glucosylceramide in glycosphingolipid synthesis. Journal of Cell Biology, 179(1), 101-115.


Cite as: https://hdl.handle.net/21.11116/0000-0001-0F80-E
Abstract
Glycosphingolipids are controlled by the spatial organization of their metabolism and by trans port specifi city. Using immunoelectron microscopy, we localize to the Golgi stack the glycosyltransferases that produce glucosylceramide (GlcCer), lactosylceramide (LacCer), and GM3. GlcCer is synthesized on the cytosolic side and must translocate across to the Golgi lumen for LacCer synthesis. However, only very little natural GlcCer translocates across the Golgi in vitro. As GlcCer reaches the cell surface when Golgi vesicular traffi cking is inhibited, it must translocate across a post-Golgi membrane. Concanamycin, a vacuolar proton pump inhibitor, blocks translocation independently of multidrug transporters that are known to translocate short-chain GlcCer. Concanamycin did not reduce LacCer and GM3 synthesis. Thus, GlcCer destined for glycolipid synthesis follows a different pathway and transports back into the endoplasmic reticulum (ER) via the late Golgi protein FAPP2. FAPP2 knockdown strongly reduces GM3 synthesis. Overall, we show that newly synthesized GlcCer enters two pathways: one toward the noncytosolic surface of a post-Golgi membrane and one via the ER toward the Golgi lumen LacCer synthase.