Yeast translation elongation factor eEF3 promotes late stages of tRNA translocation.
Yeast translation elongation factor eEF3 promotes late stages of tRNA translocation.
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DOI：
10.15252/embj.2020106449
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发表时间：
2021-03-15
期刊：
影响因子：
--
通讯作者：
Wilson DN
中科院分区：
文献类型：
--
作者：
Ranjan N;Pochopien AA;Chih-Chien Wu C;Beckert B;Blanchet S;Green R;V Rodnina M;Wilson DN
除了保守的翻译延伸因子eEF1a和eEF2外，真菌还需要第三个必需的延伸因子eEF3。虽然eEF3参与了核糖体A和E位点的tRNA结合和释放，但其确切的作用机制尚不清楚。在这里，我们证明eEF3通过促进tRNA从E位点解离而作用于mRNA-tRNA易位步骤，但不依赖于氨基酰-tRNA募集到A位点。体内eEF3的耗尽会导致翻译延伸的普遍放缓，这是由于占据了A位点的核糖体的积累。对天然eEF3-核糖体复合体的冷冻-EM分析表明，eEF3通过有利于非旋转的核糖体状态以及通过打开L1柄释放E-位tRNA来促进后期的转位步骤。此外，我们的分析提供了对新的翻译延伸状态的结构洞察，使得能够呈现修订的酵母翻译延伸周期。快速动力学、核糖体图谱和冷冻-EM结构的组合揭示了eEF3在核糖体转位/翻译的后期步骤中需要S。
In addition to the conserved translation elongation factors eEF1A and eEF2, fungi require a third essential elongation factor, eEF3. While eEF3 has been implicated in tRNA binding and release at the ribosomal A and E sites, its exact mechanism of action is unclear. Here, we show that eEF3 acts at the mRNA–tRNA translocation step by promoting the dissociation of the tRNA from the E site, but independent of aminoacyl‐tRNA recruitment to the A site. Depletion of eEF3 in vivo leads to a general slowdown in translation elongation due to accumulation of ribosomes with an occupied A site. Cryo‐EM analysis of native eEF3‐ribosome complexes shows that eEF3 facilitates late steps of translocation by favoring non‐rotated ribosomal states, as well as by opening the L1 stalk to release the E‐site tRNA. Additionally, our analysis provides structural insights into novel translation elongation states, enabling presentation of a revised yeast translation elongation cycle. A combination of rapid kinetics, ribosome profiling, and cryo‐EM structures reveals eEF3’s requirement during late steps of ribosomal translocation/ translation.
DOI：
10.1007/978-1-61779-034-8_13
发表时间：
2011
期刊：
Methods in molecular biology (Clifton, N.J.)
影响因子：
--
作者：
Park, Jong Hwan;Wolff, Edith C;Park, Myung Hee
通讯作者：
Park, Myung Hee
DOI：
10.1007/978-1-61779-034-8_12
发表时间：
2011
期刊：
Methods in molecular biology (Clifton, N.J.)
影响因子：
--
作者：
Wolff, Edith C;Lee, Seung Bum;Park, Myung Hee
通讯作者：
Park, Myung Hee