Purified EDEM3 or EDEM1 alone produces determinant oligosaccharide structures from M8B in mammalian glycoprotein ERAD
- Kyoto University, Japan
- Nagoya City University, Japan
- Hokkaido University, Japan
- National Institute of Health Sciences, Japan
- Osaka University, Japan
Abstract
Sequential mannose trimming of N-glycan, from M9 to M8B and then to oligosaccharides exposing the a1,6-linked mannosyl residue (M7A, M6 and M5), facilitates endoplasmic reticulum-associated degradation of misfolded glycoproteins (gpERAD). We previously showed that EDEM2 stably disulfide-bonded to the thioredoxin domain-containing protein TXNDC11 is responsible for the first step (George et al., 2020). Here, we show that EDEM3 and EDEM1 are responsible for the second step. Incubation of pyridylamine-labeled M8B with purified EDEM3 alone produced M7 (M7A and M7C), M6 and M5. EDEM1 showed a similar tendency, although much lower amounts of M6 and M5 were produced. Thus, EDEM3 is a major a1,2-mannosidase for the second step from M8B. Both EDEM3 and EDEM1 trimmed M8B from a glycoprotein efficiently. Our confirmation of the Golgi localization of MAN1B indicates that no other a1,2-mannosidase is required for gpERAD. Accordingly, we have established the entire route of oligosaccharide processing and the enzymes responsible.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 1S1, 2, 2S1, 4, 5, 6 and 7.
Article and author information
Author details
Funding
MEXT, Japan (18K06216)
- Satoshi Ninagawa
Kobayashi Foundation
- Satoshi Ninagawa
MEXT, Japa (17H06414)
- Hirokazu Yagi
MEXT, Japan (21H02625)
- Hirokazu Yagi
MEXT, Japan (19K06658)
- Tokiro Ishikawa
MEXT, Japan (20K21495)
- Koichi Kato
MEXT, Japan (18K06110)
- Tetsuya Okada
MEXT, Japan (17H01432)
- Kazutoshi Mori
MEXT, Japan (17H06419)
- Kazutoshi Mori
Takeda Science Foundation
- Satoshi Ninagawa
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Adam Linstedt, Carnegie Mellon University, United States
Version history
- Received: May 29, 2021
- Accepted: October 7, 2021
- Accepted Manuscript published: October 26, 2021 (version 1)
- Version of Record published: November 5, 2021 (version 2)
Copyright
© 2021, George 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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Purified EDEM3 or EDEM1 alone produces determinant oligosaccharide structures from M8B in mammalian glycoprotein ERAD
eLife 10:e70357.
https://doi.org/10.7554/eLife.70357
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