The spatial separation of processing and transport functions to the interior and periphery of the Golgi stack
- Nanyang Technological University, Singapore
Abstract
It is unclear how the two principal functions of the Golgi complex, processing and transport, are spatially organized. Studying such spatial organization by optical imaging is challenging, partially due to the dense packing of stochastically oriented Golgi stacks. Using super-resolution microscopy and markers such as Giantin, we developed a method to identify en face and side views of individual nocodazole-induced Golgi mini-stacks. Our imaging uncovered that Golgi enzymes preferentially localize to the cisternal interior, appearing as a central disk or inner-ring, whereas components of the trafficking machinery reside at the periphery of the stack, including the cisternal rim. Interestingly, conventional secretory cargos appeared at the cisternal interior during their intra-Golgi trafficking and transiently localized to the cisternal rim before exiting the Golgi. In contrast, bulky cargos were found only at the rim. Our study therefore directly demonstrates the spatial separation of processing and transport functions within the Golgi complex.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Ministry of Education - Singapore (Tier1 RG132/15)
- Sara Sandin
- Lei Lu
National Medical Research Council-Singapore (NMRC/CBRG/007/2012)
- Lei Lu
Ministry of Education - Singapore (Tier1 RG35/17)
- Sara Sandin
- Lei Lu
Ministry of Education - Singapore (Tier1 RG48/13)
- Sara Sandin
- Lei Lu
Ministry of Education - Singapore (Tier2 MOE2015-T2-2-073)
- Sara Sandin
- Lei Lu
Ministry of Education - Singapore (Tier3 MOE 2012-T3-1-001)
- Sara Sandin
- Lei Lu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Suzanne R Pfeffer, Stanford University, United States
Publication history
- Received: August 21, 2018
- Accepted: November 30, 2018
- Accepted Manuscript published: November 30, 2018 (version 1)
- Version of Record published: December 14, 2018 (version 2)
Copyright
© 2018, Tie 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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The spatial separation of processing and transport functions to the interior and periphery of the Golgi stack
eLife 7:e41301.
https://doi.org/10.7554/eLife.41301
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