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-Structure paper
タイトル | Structural insights into metazoan pretargeting GET complexes. |
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ジャーナル・号・ページ | Nat Struct Mol Biol, Vol. 28, Issue 12, Page 1029-1037, Year 2021 |
掲載日 | 2021年12月9日 |
著者 | Alexander F A Keszei / Matthew C J Yip / Ta-Chien Hsieh / Sichen Shao / |
PubMed 要旨 | Close coordination between chaperones is essential for protein biosynthesis, including the delivery of tail-anchored (TA) proteins containing a single C-terminal transmembrane domain to the ...Close coordination between chaperones is essential for protein biosynthesis, including the delivery of tail-anchored (TA) proteins containing a single C-terminal transmembrane domain to the endoplasmic reticulum (ER) by the conserved GET pathway. For successful targeting, nascent TA proteins must be promptly chaperoned and loaded onto the cytosolic ATPase Get3 through a transfer reaction involving the chaperone SGTA and bridging factors Get4, Ubl4a and Bag6. Here, we report cryo-electron microscopy structures of metazoan pretargeting GET complexes at 3.3-3.6 Å. The structures reveal that Get3 helix 8 and the Get4 C terminus form a composite lid over the Get3 substrate-binding chamber that is opened by SGTA. Another interaction with Get4 prevents formation of Get3 helix 4, which links the substrate chamber and ATPase domain. Both interactions facilitate TA protein transfer from SGTA to Get3. Our findings show how the pretargeting complex primes Get3 for coordinated client loading and ER targeting. |
リンク | Nat Struct Mol Biol / PubMed:34887561 / PubMed Central |
手法 | EM (単粒子) |
解像度 | 3.3 - 4.1 Å |
構造データ | EMDB-24700, PDB-7ru9: EMDB-24701, PDB-7rua: EMDB-24702, PDB-7ruc: EMDB-24703: EMDB-24704: |
化合物 | ChemComp-ATP: ChemComp-MG: ChemComp-ZN: |
由来 |
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キーワード | CHAPERONE / ATPase / complex / membrane protein chaperone |