論文 - 詳細
| RRC ID | 53577 |
|---|---|
| 著者 | McClory SP, Devaraj A, Fredrick K. |
| タイトル | Distinct functional classes of ram mutations in 16S rRNA. |
| ジャーナル | RNA |
| Abstract |
During decoding, the ribosome selects the correct (cognate) aminoacyl-tRNA (aa-tRNA) from a large pool of incorrect aa-tRNAs through a two-stage mechanism. In the initial selection stage, aa-tRNA is delivered to the ribosome as part of a ternary complex with elongation factor EF-Tu and GTP. Interactions between codon and anticodon lead to activation of the GTPase domain of EF-Tu and GTP hydrolysis. Then, in the proofreading stage, aa-tRNA is released from EF-Tu and either moves fully into the A/A site (a step termed "accommodation") or dissociates from the ribosome. Cognate codon-anticodon pairing not only stabilizes aa-tRNA at both stages of decoding but also stimulates GTP hydrolysis and accommodation, allowing the process to be both accurate and fast. In previous work, we isolated a number of ribosomal ambiguity (ram) mutations in 16S rRNA, implicating particular regions of the ribosome in the mechanism of decoding. Here, we analyze a representative subset of these mutations with respect to initial selection, proofreading, RF2-dependent termination, and overall miscoding in various contexts. We find that mutations that disrupt inter-subunit bridge B8 increase miscoding in a general way, causing defects in both initial selection and proofreading. Mutations in or near the A site behave differently, increasing miscoding in a codon-anticodon-dependent manner. These latter mutations may create spurious favorable interactions in the A site for certain near-cognate aa-tRNAs, providing an explanation for their context-dependent phenotypes in the cell. |
| 巻・号 | 20(4) |
| ページ | 496-504 |
| 公開日 | 2014-4-1 |
| DOI | 10.1261/rna.043331.113 |
| PII | rna.043331.113 |
| PMID | 24572811 |
| PMC | PMC3964911 |
| MeSH | Anticodon / genetics* Codon / genetics* Guanosine Triphosphate / metabolism Kinetics Models, Molecular Mutation / genetics* Nucleic Acid Conformation Peptide Termination Factors / chemistry Peptide Termination Factors / genetics Peptide Termination Factors / metabolism Protein Biosynthesis RNA, Messenger / genetics RNA, Ribosomal, 16S / chemistry RNA, Ribosomal, 16S / genetics* RNA, Ribosomal, 16S / metabolism RNA, Transfer, Amino Acyl / chemistry RNA, Transfer, Amino Acyl / genetics* RNA, Transfer, Amino Acyl / metabolism Ribosomes / chemistry Ribosomes / genetics Ribosomes / metabolism* |
| IF | 4.32 |
| 引用数 | 11 |
| オルトメトリクス指標 |
オルトメトリクス指標項目
|
| 最多言及媒体 | X(Twitter) |
| 各媒体での言及数の合計 | 6 |
| 過去6か月間でのオルトメトリクス指標の変動値 | 0.0 |
| リソース情報 | |
| 原核生物(大腸菌) | |