Messenger RNA conformations in the ribosomal E site revealed by X-ray crystallography - PubMed (original) (raw)

Messenger RNA conformations in the ribosomal E site revealed by X-ray crystallography

Lasse Jenner et al. EMBO Rep. 2007 Sep.

Abstract

A comparison of messenger RNA in X-ray crystal structures of 70S ribosomal complexes in the initiation, post-initiation and elongation states of translation shows distinct conformational differences in the exit (E) codon. Here, we present structural evidence indicating that, after the initiation event, the E codon nucleotides relax and form a classical A-helical conformation. This conformation is similar to that of the P and A codons, and is favourable for establishing Watson-Crick interactions with the anticodon of E-site transfer RNA.

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Figures

Figure 1

Figure 1

Codon–anticodon interaction in the E site. (A,B) Structure of E, P and A codons in initiation (A) and post-initiation complexes (B). Sequences of the messenger RNA (mRNA) and the Shine–Dalgarno (SD) duplex (in red) are also shown. (C,D) E-site tRNA interaction with the E anticodon in initiation (C) and post-initiation (D) complexes. The E codon can adopt the classical A-helical conformation that enables base pairing with the anticodon of E-site tRNA only in the post-initiation complex. (E) Fourier (_F_o−_F_c) electron density map calculated at a resolution of 5.5 Å with E-site tRNA and mRNA omitted from the model. E site, exit site.

Figure 2

Figure 2

A detailed view of the ribosomal environment of the E codon in the post-initiation complex. Nucleotides directly involved in the stabilization of the E codon triplet structure are shown as yellow spheres. The residues of the S7 β-hairpin (shown as green spheres) are not in direct contact with the E codon, but are instead interacting with the upstream bases. E, exit site; h, helix; mRNA, messenger RNA; tRNA, transfer RNA.

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References

    1. Agrawal RK, Penczek P, Grassucci RA, Li Y, Leith A, Nierhaus KH, Frank J (1996) Direct visualization of A-, P-, and E-site transfer RNAs in the Escherichia coli ribosome. Science 271: 1000–1002 - PubMed
    1. Agrawal RK, Spahn MTC, Penczek P, Grassucci RA, Nierhaus KU, Franck J (2000) Visualization of tRNA movements on the Escherichia coli 70S ribosome during the elongation cycle. J Cell Biol 150: 447–459 - PMC - PubMed
    1. Berk V, Zhang W, Pai RD, Cate JH (2005) Structural basis for mRNA and tRNA positioning on the ribosome. Proc Natl Acad Sci USA 103: 15830–15834 - PMC - PubMed
    1. Bocchetta M, Xiong L, Shah S, Mankin AS (2001) Interactions between 23S rRNA and tRNA in the ribosomal E site. RNA 7: 54–63 - PMC - PubMed
    1. Brünger AT et al. (1998) Crystallography & NMR system: a new software suite for macromolecular structure determination. Acta Crystallogr D 54: 905–921 - PubMed

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