ジャーナル: Proc Natl Acad Sci U S A / 年: 2022 タイトル: In situ structural analysis reveals membrane shape transitions during autophagosome formation. 著者: Anna Bieber / Cristina Capitanio / Philipp S Erdmann / Fabian Fiedler / Florian Beck / Chia-Wei Lee / Delong Li / Gerhard Hummer / Brenda A Schulman / Wolfgang Baumeister / Florian Wilfling / 要旨: Autophagosomes are unique organelles that form de novo as double-membrane vesicles engulfing cytosolic material for destruction. Their biogenesis involves membrane transformations of distinctly ...Autophagosomes are unique organelles that form de novo as double-membrane vesicles engulfing cytosolic material for destruction. Their biogenesis involves membrane transformations of distinctly shaped intermediates whose ultrastructure is poorly understood. Here, we combine cell biology, correlative cryo-electron tomography (cryo-ET), and extensive data analysis to reveal the step-by-step structural progression of autophagosome biogenesis at high resolution directly within yeast cells. The analysis uncovers an unexpectedly thin intermembrane distance that is dilated at the phagophore rim. Mapping of individual autophagic structures onto a timeline based on geometric features reveals a dynamical change of membrane shape and curvature in growing phagophores. Moreover, our tomograms show the organelle interactome of growing autophagosomes, highlighting a polar organization of contact sites between the phagophore and organelles, such as the vacuole and the endoplasmic reticulum (ER). Collectively, these findings have important implications for the contribution of different membrane sources during autophagy and for the forces shaping and driving phagophores toward closure without a templating cargo.
A: 13066.24 Å / B: 13066.24 Å / C: 4815.36 Å α=β=γ: 90.0 °
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添付データ
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試料の構成要素
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全体 : In situ cryo-electron tomogram of a bulk autophagy phagophore in ...
全体
名称: In situ cryo-electron tomogram of a bulk autophagy phagophore in S. cerevisiae #4
要素
細胞: In situ cryo-electron tomogram of a bulk autophagy phagophore in S. cerevisiae #4
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超分子 #1: In situ cryo-electron tomogram of a bulk autophagy phagophore in ...
超分子
名称: In situ cryo-electron tomogram of a bulk autophagy phagophore in S. cerevisiae #4 タイプ: cell / ID: 1 / 親要素: 0 詳細: Phagophore in the cytoplasm next to the vacuole. The position of the phagophore corresponds to eGFP-Atg8 signal detected by cryo-fluorescence microscopy.
凍結剤: ETHANE-PROPANE / チャンバー内温度: 295 K / 装置: FEI VITROBOT MARK IV
詳細
S. cerevisiae. 2 hours starvation in SD-N.
切片作成
集束イオンビーム - 装置: OTHER / 集束イオンビーム - イオン: OTHER / 集束イオンビーム - 電圧: 30 / 集束イオンビーム - 電流: 0.3 / 集束イオンビーム - 時間: 2400 / 集束イオンビーム - 温度: 91 K / 集束イオンビーム - Initial thickness: 7000 / 集束イオンビーム - 最終 厚さ: 150 集束イオンビーム - 詳細: Correlative FIB-milling. The lamella was prepared in the location of fluorescence signal.. The value given for _em_focused_ion_beam.instrument is Other. This is not ...集束イオンビーム - 詳細: Correlative FIB-milling. The lamella was prepared in the location of fluorescence signal.. The value given for _em_focused_ion_beam.instrument is Other. This is not in a list of allowed values {'DB235', 'OTHER'} so OTHER is written into the XML file.