Stacking the odds for Golgi cisternal maturation
Abstract
What is the minimal set of cell-biological ingredients needed to generate a Golgi apparatus? The compositions of eukaryotic organelles arise through a process of molecular exchange via vesicle traffic. Here we statistically sample tens of thousands of homeostatic vesicle traffic networks generated by realistic molecular rules governing vesicle budding and fusion. Remarkably, the plurality of these networks contain chains of compartments that undergo creation, compositional maturation, and dissipation, coupled by molecular recycling along retrograde vesicles. This motif precisely matches the cisternal maturation model of the Golgi, which was developed to explain many observed aspects of the eukaryotic secretory pathway. In our analysis cisternal maturation is a robust consequence of vesicle traffic homeostasis, independent of the underlying details of molecular interactions or spatial stacking. This architecture may have been exapted rather than selected for its role in the secretion of large cargo.
Article and author information
Author details
Funding
Wellcome Trust-DBT India Alliance (Intermediate Fellowship 500103/Z/09/Z)
- Mukund Thattai
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Benjamin S Glick, The University of Chicago, United States
Version history
- Received: March 20, 2016
- Accepted: August 18, 2016
- Accepted Manuscript published: August 19, 2016 (version 1)
- Version of Record published: September 6, 2016 (version 2)
Copyright
© 2016, Mani & Thattai
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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