EMD-24282
Post-2S intermediate of the Tetrahymena group I intron, symmetry-expanded monomer from a synthetic dimeric construct
EMD-24282
Single-particle3.68 Å
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Map released: 04/05/2022
Last modified: 05/06/2024
Sample Organism:
Tetrahymena thermophila
Sample: Post-2S intermediate of Tetrahymena group I intron, symmetry-expanded monomer from a synthetic dimeric construct
Fitted models: 7r6m (Avg. Q-score: 0.389)
Deposition Authors: Thelot F, Liu D
Sample: Post-2S intermediate of Tetrahymena group I intron, symmetry-expanded monomer from a synthetic dimeric construct
Fitted models: 7r6m (Avg. Q-score: 0.389)
Deposition Authors: Thelot F, Liu D
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Sub-3- angstrom cryo-EM structure of RNA enabled by engineered homomeric self-assembly.
Abstract:
High-resolution structural studies are essential for understanding the folding and function of diverse RNAs. Herein, we present a nanoarchitectural engineering strategy for efficient structural determination of RNA-only structures using single-particle cryogenic electron microscopy (cryo-EM). This strategy-ROCK (RNA oligomerization-enabled cryo-EM via installing kissing loops)-involves installing kissing-loop sequences onto the functionally nonessential stems of RNAs for homomeric self-assembly into closed rings with multiplied molecular weights and mitigated structural flexibility. ROCK enables cryo-EM reconstruction of the Tetrahymena group I intron at 2.98-Å resolution overall (2.85 Å for the core), allowing de novo model building of the complete RNA, including the previously unknown peripheral domains. ROCK is further applied to two smaller RNAs-the Azoarcus group I intron and the FMN riboswitch, revealing the conformational change of the former and the bound ligand in the latter. ROCK holds promise to greatly facilitate the use of cryo-EM in RNA structural studies.
High-resolution structural studies are essential for understanding the folding and function of diverse RNAs. Herein, we present a nanoarchitectural engineering strategy for efficient structural determination of RNA-only structures using single-particle cryogenic electron microscopy (cryo-EM). This strategy-ROCK (RNA oligomerization-enabled cryo-EM via installing kissing loops)-involves installing kissing-loop sequences onto the functionally nonessential stems of RNAs for homomeric self-assembly into closed rings with multiplied molecular weights and mitigated structural flexibility. ROCK enables cryo-EM reconstruction of the Tetrahymena group I intron at 2.98-Å resolution overall (2.85 Å for the core), allowing de novo model building of the complete RNA, including the previously unknown peripheral domains. ROCK is further applied to two smaller RNAs-the Azoarcus group I intron and the FMN riboswitch, revealing the conformational change of the former and the bound ligand in the latter. ROCK holds promise to greatly facilitate the use of cryo-EM in RNA structural studies.