Sphingomyelin metabolism controls the shape and function of the Golgi cisternae
Abstract
The flat Golgi cisterna is a highly conserved feature of eukaryotic cells, but how is this morphology achieved and is it related to its function in cargo sorting and export? A physical model of cisterna morphology led us to propose that sphingomyelin (SM) metabolism at the trans-Golgi membranes in mammalian cells essentially controls the structural features of a Golgi cisterna by regulating its association to curvature-generating proteins. An experimental test of this hypothesis revealed that affecting SM homeostasis converted flat cisternae into highly curled membranes with a concomitant dissociation of membrane curvature-generating proteins. These data lend support to our hypothesis that SM metabolism controls the structural organization of a Golgi cisterna. Together with our previously presented role of SM in controlling the location of proteins involved in glycosylation and vesicle formation, our data reveal the significance of SM metabolism in the structural organization and function of Golgi cisternae.
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Author details
Funding
Ministerio de Economía y Competitividad (Severo Ochoa Programme SEV-2015-240522)
- Felix Campelo
- María García-Parajo
H2020 European Research Council (Advanced Grant 268692)
- Vivek Malhotra
Ministerio de Economía y Competitividad (Severo Ochoa Programme SEV-2012-0208)
- Vivek Malhotra
Ministerio de Economía y Competitividad (BFU2015-73288-JIN AEI/FED)
- Felix Campelo
- María García-Parajo
Fundación Cellex
- Felix Campelo
- María García-Parajo
Human Frontier Science Program (GA RGP0027/2012)
- María García-Parajo
European Commission (FP7-NANO-VISTA GA 288263)
- María García-Parajo
Institució Catalana de Recerca i Estudis Avançats
- María García-Parajo
- Vivek Malhotra
Israel Science Foundation (758/11)
- Michael M Kozlov
Ministerio de Economía y Competitividad (Plan Nacional FIS2014-56107-R)
- María García-Parajo
Ministerio de Economía y Competitividad (Plan Nacional BFU2013-44188-P)
- Vivek Malhotra
Ministerio de Economía y Competitividad (Consolider CSD2009-00016)
- Vivek Malhotra
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Patricia Bassereau, Institut Curie, France
Publication history
- Received: December 23, 2016
- Accepted: May 4, 2017
- Accepted Manuscript published: May 13, 2017 (version 1)
- Version of Record published: June 7, 2017 (version 2)
Copyright
© 2017, Campelo et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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