Cryo-electron microscopy structure and translocation mechanism of the crenarchaeal ribosome.
Cryo-electron microscopy structure and translocation mechanism of the crenarchaeal ribosome.
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DOI：
10.1093/nar/gkad661
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发表时间：
2023-09-22
影响因子：
14.9
通讯作者：
中科院分区：
文献类型：
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作者：
古生代核糖体具有许多区域特异性特征；然而，我们对这些结构的了解是有限的。我们用低温电子显微镜(CRYO-EM)观察了古核糖体的10种结构，分辨率为2.7-5.7。我们在亚基结构中观察到核糖体RNA(RRNA)的H68和H44不稳定的构象，这可能干扰亚基结合。这些亚基结构提供了12个rRNA扩展片段和3个新的r-蛋白的模型。此外，50S-aRF1复合结构显示了aRF1独特的结构域取向，这可能解释了翻译终止后P位点转移RNA(TRNA)的释放。SAC 70S复合体在tRNA易位反应的七个不同步骤中被捕获，证实了古生物核糖体易位过程中的保守结构特征。在aEF2参与的70S核糖体复合体中，基于30S头部结构域的三维冷冻-EM数据分类发现了两个新的易位中间体，30S头部结构域倾斜了5-6°，使其能够从移位的tRNA中解脱出来，并在易位后释放。此外，我们观察到在核糖体结合和从三种不同状态转换的过程中aEF2的构象变化。我们的结构和生化数据为古生物翻译和核糖体易位提供了新的见解。
Archaeal ribosomes have many domain-specific features; however, our understanding of these structures is limited. We present 10 cryo-electron microscopy (cryo-EM) structures of the archaeal ribosome from crenarchaeota Sulfolobus acidocaldarius (Sac) at 2.7–5.7 Å resolution. We observed unstable conformations of H68 and h44 of ribosomal RNA (rRNA) in the subunit structures, which may interfere with subunit association. These subunit structures provided models for 12 rRNA expansion segments and 3 novel r-proteins. Furthermore, the 50S–aRF1 complex structure showed the unique domain orientation of aRF1, possibly explaining P-site transfer RNA (tRNA) release after translation termination. Sac 70S complexes were captured in seven distinct steps of the tRNA translocation reaction, confirming conserved structural features during archaeal ribosome translocation. In aEF2-engaged 70S ribosome complexes, 3D classification of cryo-EM data based on 30S head domain identified two new translocation intermediates with 30S head domain tilted 5–6° enabling its disengagement from the translocated tRNA and its release post-translocation. Additionally, we observed conformational changes to aEF2 during ribosome binding and switching from three different states. Our structural and biochemical data provide new insights into archaeal translation and ribosome translocation.
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影响因子：
64.8
作者：
Djumagulov M;Demeshkina N;Jenner L;Rozov A;Yusupov M;Yusupova G
通讯作者：
Yusupova G
DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
Emsley, P;Cowtan, K
通讯作者：
Cowtan, K
影响因子：
16.6
作者：
Carbone CE;Loveland AB;Gamper HB Jr;Hou YM;Demo G;Korostelev AA
通讯作者：
Korostelev AA
DOI：
10.1126/science.1202692
发表时间：
2011-05-20
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Dunkle JA;Wang L;Feldman MB;Pulk A;Chen VB;Kapral GJ;Noeske J;Richardson JS;Blanchard SC;Cate JH
通讯作者：
Cate JH
DOI：
10.1126/science.1179709
发表时间：
2009-10-30
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Gao YG;Selmer M;Dunham CM;Weixlbaumer A;Kelley AC;Ramakrishnan V
通讯作者：
Ramakrishnan V