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-Structure paper
タイトル | Structural insights into initial and intermediate steps of the ribosome-recycling process. |
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ジャーナル・号・ページ | EMBO J, Vol. 31, Issue 7, Page 1836-1846, Year 2012 |
掲載日 | 2012年4月4日 |
著者 | Takeshi Yokoyama / Tanvir R Shaikh / Nobuhiro Iwakura / Hideko Kaji / Akira Kaji / Rajendra K Agrawal / |
PubMed 要旨 | The ribosome-recycling factor (RRF) and elongation factor-G (EF-G) disassemble the 70S post-termination complex (PoTC) into mRNA, tRNA, and two ribosomal subunits. We have determined cryo-electron ...The ribosome-recycling factor (RRF) and elongation factor-G (EF-G) disassemble the 70S post-termination complex (PoTC) into mRNA, tRNA, and two ribosomal subunits. We have determined cryo-electron microscopic structures of the PoTC·RRF complex, with and without EF-G. We find that domain II of RRF initially interacts with universally conserved residues of the 23S rRNA helices 43 and 95, and protein L11 within the 50S ribosomal subunit. Upon EF-G binding, both RRF and tRNA are driven towards the tRNA-exit (E) site, with a large rotational movement of domain II of RRF towards the 30S ribosomal subunit. During this intermediate step of the recycling process, domain II of RRF and domain IV of EF-G adopt hitherto unknown conformations. Furthermore, binding of EF-G to the PoTC·RRF complex reverts the ribosome from ratcheted to unratcheted state. These results suggest that (i) the ribosomal intersubunit reorganizations upon RRF binding and subsequent EF-G binding could be instrumental in destabilizing the PoTC and (ii) the modes of action of EF-G during tRNA translocation and ribosome-recycling steps are markedly different. |
リンク | EMBO J / PubMed:22388519 / PubMed Central |
手法 | EM (単粒子) |
解像度 | 9.9 - 11.1 Å |
構造データ | EMDB-1915: Initial binding position of RRF on the post-termination complex EMDB-1916: Initial binding conformation of RRF on the post-termination complex |
由来 |
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キーワード | TRANSLATION / ribosome / ribosome recycling factor / Elongation Factor G |