6ZU9
Structure of a yeast ABCE1-bound 48S initiation complex
Summary for 6ZU9
Entry DOI | 10.2210/pdb6zu9/pdb |
Related | 6zce |
EMDB information | 11439 |
Descriptor | 18S ribosomal RNA, 40S ribosomal protein S11-A, 40S ribosomal protein S13, ... (49 entities in total) |
Functional Keywords | translation, initiation, ribosome recycling, abc proteins, ribosome |
Biological source | Saccharomyces cerevisiae (strain ATCC 204508 / S288c) More |
Total number of polymer chains | 44 |
Total formula weight | 1681179.45 |
Authors | Kratzat, H.,Mackens-Kiani, T.,Cheng, J.,Berninghausen, O.,Becker, T.,Beckmann, R. (deposition date: 2020-07-22, release date: 2020-10-28, Last modification date: 2024-05-01) |
Primary citation | Kratzat, H.,Mackens-Kiani, T.,Ameismeier, M.,Potocnjak, M.,Cheng, J.,Dacheux, E.,Namane, A.,Berninghausen, O.,Herzog, F.,Fromont-Racine, M.,Becker, T.,Beckmann, R. A structural inventory of native ribosomal ABCE1-43S pre-initiation complexes. Embo J., 40:e105179-e105179, 2021 Cited by PubMed Abstract: 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. PubMed: 33289941DOI: 10.15252/embj.2020105179 PDB entries with the same primary citation |
Experimental method | ELECTRON MICROSCOPY (6.2 Å) |
Structure validation
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