Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s
Autophagy is an essential catabolic pathway which sequesters and engulfs cytosolic substrates via autophagosomes, unique double-membraned structures. ATG8 proteins are ubiquitin-like proteins recruited to autophagosome membranes by lipidation at the C-terminus. ATG8s recruit substrates, such as p62,...
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| Format: | Article |
| Language: | English |
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eLife Sciences Publications Ltd
2023-06-01
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| Series: | eLife |
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| Online Access: | https://elifesciences.org/articles/89185 |
| _version_ | 1827918064526557184 |
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| author | Wenxin Zhang Taki Nishimura Deepanshi Gahlot Chieko Saito Colin Davis Harold BJ Jefferies Anne Schreiber Lipi Thukral Sharon A Tooze |
| author_facet | Wenxin Zhang Taki Nishimura Deepanshi Gahlot Chieko Saito Colin Davis Harold BJ Jefferies Anne Schreiber Lipi Thukral Sharon A Tooze |
| author_sort | Wenxin Zhang |
| collection | DOAJ |
| description | Autophagy is an essential catabolic pathway which sequesters and engulfs cytosolic substrates via autophagosomes, unique double-membraned structures. ATG8 proteins are ubiquitin-like proteins recruited to autophagosome membranes by lipidation at the C-terminus. ATG8s recruit substrates, such as p62, and play an important role in mediating autophagosome membrane expansion. However, the precise function of lipidated ATG8 in expansion remains obscure. Using a real-time in vitro lipidation assay, we revealed that the N-termini of lipidated human ATG8s (LC3B and GABARAP) are highly dynamic and interact with the membrane. Moreover, atomistic MD simulation and FRET assays indicate that N-termini of LC3B and GABARAP associate in cis on the membrane. By using non-tagged GABARAPs, we show that GABARAP N-terminus and its cis-membrane insertion are crucial to regulate the size of autophagosomes in cells irrespectively of p62 degradation. Our study provides fundamental molecular insights into autophagosome membrane expansion, revealing the critical and unique function of lipidated ATG8. |
| first_indexed | 2024-03-13T03:37:24Z |
| format | Article |
| id | doaj.art-532bcd67647149c3ad75104862f8b1ba |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-03-13T03:37:24Z |
| publishDate | 2023-06-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-532bcd67647149c3ad75104862f8b1ba2023-06-23T14:28:24ZengeLife Sciences Publications LtdeLife2050-084X2023-06-011210.7554/eLife.89185Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8sWenxin Zhang0https://orcid.org/0000-0002-7657-4495Taki Nishimura1https://orcid.org/0000-0003-4019-5984Deepanshi Gahlot2https://orcid.org/0000-0002-2681-8818Chieko Saito3Colin Davis4Harold BJ Jefferies5Anne Schreiber6Lipi Thukral7https://orcid.org/0000-0002-1961-039XSharon A Tooze8https://orcid.org/0000-0002-2182-3116Molecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, London, United KingdomMolecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, London, United Kingdom; Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, Japan; PRESTO, Japan Science and Technology Agency, Tokyo, JapanCSIR-Institute of Genomics and Integrative Biology, New Delhi, India; Academy of Scientific and Innovative Research, Ghaziabad, IndiaDepartment of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo, JapanCellular Degradation Systems Laboratory, The Francis Crick Institute, London, United KingdomMolecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, London, United KingdomCellular Degradation Systems Laboratory, The Francis Crick Institute, London, United KingdomCSIR-Institute of Genomics and Integrative Biology, New Delhi, India; Academy of Scientific and Innovative Research, Ghaziabad, IndiaMolecular Cell Biology of Autophagy Laboratory, The Francis Crick Institute, London, United KingdomAutophagy is an essential catabolic pathway which sequesters and engulfs cytosolic substrates via autophagosomes, unique double-membraned structures. ATG8 proteins are ubiquitin-like proteins recruited to autophagosome membranes by lipidation at the C-terminus. ATG8s recruit substrates, such as p62, and play an important role in mediating autophagosome membrane expansion. However, the precise function of lipidated ATG8 in expansion remains obscure. Using a real-time in vitro lipidation assay, we revealed that the N-termini of lipidated human ATG8s (LC3B and GABARAP) are highly dynamic and interact with the membrane. Moreover, atomistic MD simulation and FRET assays indicate that N-termini of LC3B and GABARAP associate in cis on the membrane. By using non-tagged GABARAPs, we show that GABARAP N-terminus and its cis-membrane insertion are crucial to regulate the size of autophagosomes in cells irrespectively of p62 degradation. Our study provides fundamental molecular insights into autophagosome membrane expansion, revealing the critical and unique function of lipidated ATG8.https://elifesciences.org/articles/89185autophagycis-membrane associationmembrane expansionautophagosome sizereal-time lipidation assayatomistic MD simulation |
| spellingShingle | Wenxin Zhang Taki Nishimura Deepanshi Gahlot Chieko Saito Colin Davis Harold BJ Jefferies Anne Schreiber Lipi Thukral Sharon A Tooze Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s eLife autophagy cis-membrane association membrane expansion autophagosome size real-time lipidation assay atomistic MD simulation |
| title | Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s |
| title_full | Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s |
| title_fullStr | Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s |
| title_full_unstemmed | Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s |
| title_short | Autophagosome membrane expansion is mediated by the N-terminus and cis-membrane association of human ATG8s |
| title_sort | autophagosome membrane expansion is mediated by the n terminus and cis membrane association of human atg8s |
| topic | autophagy cis-membrane association membrane expansion autophagosome size real-time lipidation assay atomistic MD simulation |
| url | https://elifesciences.org/articles/89185 |
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