TANGO1 recruits ERGIC membranes to the endoplasmic reticulum for procollagen export
Abstract
Previously we showed that membrane fusion is required for TANGO1-dependent export of procollagen VII from the endoplasmic reticulum (ER) (Nogueira et al., 2014). Along with the t-SNARE Syntaxin 18, we now reveal the complete complement of SNAREs required in this process, t-SNAREs BNIP1 and USE1, and v-SNARE YKT6. TANGO1 recruits YKT6-containing ER Golgi Intermediate Compartment (ERGIC) membranes to procollagen VII-enriched patches on the ER. Moreover residues 1214-1396, that include the first coiled coil of TANGO1, specifically recruit ERGIC membranes even when targeted to mitochondria. TANGO1 is thus pivotal in concentrating procollagen VII in the lumen and recruiting ERGIC membranes on the cytoplasmic surface of the ER. Our data reveal that growth of a mega transport carrier for collagen export from the ER is not by acquisition of a larger patch of ER membrane, but instead by addition of ERGIC membranes to procollagen-enriched domains of the ER by a TANGO-mediated process.
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Reviewing Editor
- Suzanne R Pfeffer, Stanford University School of Medicine, United States
Version history
- Received: August 20, 2015
- Accepted: November 13, 2015
- Accepted Manuscript published: November 14, 2015 (version 1)
- Version of Record published: December 31, 2015 (version 2)
Copyright
© 2015, Santos 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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