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-Structure paper
タイトル | A structural inventory of native ribosomal ABCE1-43S pre-initiation complexes. |
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ジャーナル・号・ページ | EMBO J, Vol. 40, Issue 1, Page e105179, Year 2021 |
掲載日 | 2021年1月4日 |
![]() | Hanna Kratzat / Timur Mackens-Kiani / Michael Ameismeier / Mia Potocnjak / Jingdong Cheng / Estelle Dacheux / Abdelkader Namane / Otto Berninghausen / Franz Herzog / Micheline Fromont-Racine / Thomas Becker / Roland Beckmann / ![]() ![]() |
PubMed 要旨 | In eukaryotic translation, termination and ribosome recycling phases are linked to subsequent initiation of a new round of translation by persistence of several factors at ribosomal sub-complexes. ...In eukaryotic translation, termination and ribosome recycling phases are linked to subsequent initiation of a new round of translation by persistence of several factors at ribosomal sub-complexes. These comprise/include the large eIF3 complex, eIF3j (Hcr1 in yeast) and the ATP-binding cassette protein ABCE1 (Rli1 in yeast). The ATPase is mainly active as a recycling factor, but it can remain bound to the dissociated 40S subunit until formation of the next 43S pre-initiation complexes. However, its functional role and native architectural context remains largely enigmatic. Here, we present an architectural inventory of native yeast and human ABCE1-containing pre-initiation complexes by cryo-EM. We found that ABCE1 was mostly associated with early 43S, but also with later 48S phases of initiation. It adopted a novel hybrid conformation of its nucleotide-binding domains, while interacting with the N-terminus of eIF3j. Further, eIF3j occupied the mRNA entry channel via its ultimate C-terminus providing a structural explanation for its antagonistic role with respect to mRNA binding. Overall, the native human samples provide a near-complete molecular picture of the architecture and sophisticated interaction network of the 43S-bound eIF3 complex and the eIF2 ternary complex containing the initiator tRNA. |
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手法 | EM (単粒子) |
解像度 | 3.0 - 6.2 Å |
構造データ | EMDB-11160, PDB-6zce: EMDB-11439, PDB-6zu9: EMDB-11458, PDB-6zvj: EMDB-11602, PDB-7a09: EMDB-11608, PDB-7a1g: |
化合物 | ![]() ChemComp-ZN: ![]() ChemComp-ADP: ![]() ChemComp-MG: ![]() ChemComp-ATP: ![]() ChemComp-SF4: ![]() ChemComp-MET: ![]() ChemComp-GTP: |
由来 |
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![]() | RIBOSOME / Translation / Initiation / Ribosome Recycling / ABC Proteins |