9CG5 の概要
エントリーDOI | 10.2210/pdb9cg5/pdb |
関連するPDBエントリー | 9AX7 9AX8 |
EMDBエントリー | 43929 43930 45569 |
分子名称 | 50S ribosomal protein L33, 30S ribosomal protein S5, 30S ribosomal protein S6, ... (57 entities in total) |
機能のキーワード | translation initiation, trna-fmet m1, frameshifting, ribosome |
由来する生物種 | Escherichia coli 詳細 |
タンパク質・核酸の鎖数 | 54 |
化学式量合計 | 2181191.36 |
構造登録者 | |
主引用文献 | Mattingly, J.M.,Nguyen, H.A.,Roy, B.,Fredrick, K.,Dunham, C.M. Structural analysis of noncanonical translation initiation complexes. J.Biol.Chem., 300:107743-107743, 2024 Cited by PubMed Abstract: Translation initiation is a highly regulated, multi-step process which is critical for efficient and accurate protein synthesis. In bacteria, initiation begins when mRNA, initiation factors, and a dedicated initiator fMet-tRNA bind the small (30S) ribosomal subunit. Specific binding of fMet-tRNA in the peptidyl (P) site is mediated by the inspection of the fMet moiety by initiation factor IF2 and of three conserved G-C base pairs in the tRNA anticodon stem by the 30S head domain. Tandem A-minor interactions form between 16S ribosomal RNA nucleotides A1339 and G1338 and tRNA base pairs G30-C40 and G29-C41, respectively. Swapping the G30-C40 pair of tRNA with C-G reduces discrimination against the noncanonical start codon CUG in vitro, suggesting crosstalk between gripping of the anticodon stem and recognition of the start codon. Here, we solved electron cryomicroscopy structures of E. coli 70S initiation complexes containing an fMet-tRNA G30-C40 variant paired to noncanonical CUG start codon, in the presence or absence of IF2 and the non-hydrolyzable GTP analog GDPCP, alongside structures of 70S initiation complexes containing this tRNA variant paired to the canonical bacterial start codons AUG, GUG, and UUG. We find that the M1 mutation weakens A-minor interactions between tRNA and 16S nucleotides A1339 and G1338, with IF2 strengthening the interaction of G1338 with the tRNA minor groove. These structures suggest how even slight changes to the recognition of the fMet-tRNA anticodon stem by the ribosome can impact start codon selection. PubMed: 39222680DOI: 10.1016/j.jbc.2024.107743 主引用文献が同じPDBエントリー |
実験手法 | ELECTRON MICROSCOPY (2.59 Å) |
構造検証レポート
検証レポート(詳細版)
をダウンロード
