A physical mechanism of TANGO1-mediated bulky cargo export
Abstract
The endoplasmic reticulum (ER)-resident protein TANGO1 assembles into a ring around ER exit sites (ERES), and links procollagens in the ER lumen to COPII machinery, tethers, and ER-Golgi intermediate compartment (ERGIC) in the cytoplasm (Raote et al., 2018). Here we present a theoretical approach to investigate the physical mechanisms of TANGO1 ring assembly and how COPII polymerization, membrane tension, and force facilitate the formation of a transport intermediate for procollagen export. Our results indicate that a TANGO1 ring, by acting as a linactant, stabilizes the open neck of a nascent COPII bud. Elongation of such a bud into a transport intermediate commensurate with bulky procollagens is then facilitated by two complementary mechanisms: (i) by relieving membrane tension, possibly by TANGO1-mediated fusion of retrograde ERGIC membranes; and (ii) by force application. Altogether, our theoretical approach identifies key biophysical events in TANGO1-driven procollagen export.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
Government of Spain (Severo Ochoa" Programme (CEX2019-000910-S)")
- Morgan Chabanon
- Maria F Garcia-Parajo
- Felix Campelo
Spanish Government (BFU2013-44188-P)
- Ishier Raote
- Vivek Malhotra
Spanish Government (Consolider CSD2009-00016)
- Ishier Raote
- Vivek Malhotra
Spanish Government (Severo Ochoa Program SEV-2012-0208)
- Ishier Raote
- Vivek Malhotra
Spanish Government (Maria de Maeztu MDM-2015-0502)
- Vivek Malhotra
BIST (Ignite grant eTANGO)
- Ishier Raote
- Maria F Garcia-Parajo
- Vivek Malhotra
- Felix Campelo
Spanish Ministry of Science and Innovation (IJCI-2017-34751)
- Ishier Raote
Spanish Ministry of Science and Innovation (RYC-2017-22227)
- Felix Campelo
Europen Comission (CoG-681434)
- Nikhil Walani
- Marino Arroyo
Generalitat de Catalunya (2017-SGR-1278)
- Marino Arroyo
ICREA (ICREA academia)
- Marino Arroyo
Government of Spain (BFU2015-73288-JIN)
- Maria F Garcia-Parajo
- Felix Campelo
Spanish Government (Severo Ochoa Program,CEX2018-000797-S)
- Marino Arroyo
State Research Agency (PID2019-106232RB-I00/ 10.13039/501100011033)
- Morgan Chabanon
- Felix Campelo
Government of Spain (FIS2015-63550-R)
- Maria F Garcia-Parajo
- Felix Campelo
Government of Spain (FIS2017-89560-R)
- Morgan Chabanon
- Maria F Garcia-Parajo
- Felix Campelo
Fundacio Privada Cellex
- Morgan Chabanon
- Maria F Garcia-Parajo
- Felix Campelo
Fundacio Privada Mir-Puig
- Morgan Chabanon
- Maria F Garcia-Parajo
- Felix Campelo
Generalitat de Catalunya (CERCA program)
- Ishier Raote
- Morgan Chabanon
- Maria F Garcia-Parajo
- Vivek Malhotra
- Felix Campelo
European Comission (ERC Advanced Grant (GA 788546))
- Morgan Chabanon
- Maria F Garcia-Parajo
- Felix Campelo
LaserLab 4 Europe (GA 654148)
- Morgan Chabanon
- Maria F Garcia-Parajo
- Felix Campelo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Raote 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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