Department of Molecular Sociology, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438, Frankfurt am Main, Germany.
Department of Molecular Sociology, IMPRS on Cellular Biophysics, Max-von-Laue-Straße 3, 60438, Frankfurt am Main, Germany.
Nat Commun. 2022 Dec 2;13(1):7435. doi: 10.1038/s41467-022-34997-w.
Ribosomes translate genetic information into primary structure. During translation, various cofactors transiently bind to the ribosome that undergoes prominent conformational and structural changes. Different translational states of ribosomes have been well characterized in vitro. However, to which extent the known translational states are representative of the native situation inside cells has thus far only been addressed in prokaryotes. Here, we apply cryo-electron tomography to cryo-FIB milled Dictyostelium discoideum cells combined with subtomogram averaging and classification. We obtain an in situ structure that is locally resolved up to 3 Angstrom, the distribution of eukaryotic ribosome translational states, and unique arrangement of rRNA expansion segments. Our work demonstrates the use of in situ structural biology techniques for identifying distinct ribosome states within the cellular environment.
核糖体将遗传信息翻译成一级结构。在翻译过程中，各种辅助因子瞬时结合到核糖体上，核糖体发生显著的构象和结构变化。核糖体的不同翻译状态已在体外得到很好的描述。然而，到目前为止，已知的翻译状态在原核细胞中的代表性程度，仅在原核生物中得到了研究。在这里，我们应用冷冻电镜断层扫描结合亚断层平均和分类技术，对经过冷冻聚焦离子束铣削的盘基网柄菌细胞进行研究。我们获得了一个局部分辨率高达 3 埃的原位结构，以及真核核糖体翻译状态的分布和 rRNA 扩展片段的独特排列。我们的工作证明了原位结构生物学技术在识别细胞环境中不同核糖体状态方面的应用。
