|3izu, resolution 8.25Å ()|
|Non-Standard Residues:||, , , , , , , , , , , , ,|
Structural insights into cognate vs. near-cognate discrimination during decoding. This entry contains the large subunit of a ribosome programmed with a cognate codon
The structural basis of the tRNA selection process is investigated by cryo-electron microscopy of ribosomes programmed with UGA codons and incubated with ternary complex (TC) containing the near-cognate Trp-tRNA(Trp) in the presence of kirromycin. Going through more than 350 000 images and employing image classification procedures, we find approximately 8% in which the TC is bound to the ribosome. The reconstructed 3D map provides a means to characterize the arrangement of the near-cognate aa-tRNA with respect to elongation factor Tu (EF-Tu) and the ribosome, as well as the domain movements of the ribosome. One of the interesting findings is that near-cognate tRNA's acceptor stem region is flexible and CCA end becomes disordered. The data bring direct structural insights into the induced-fit mechanism of decoding by the ribosome, as the analysis of the interactions between small and large ribosomal subunit, aa-tRNA and EF-Tu and comparison with the cognate case (UGG codon) offers clues on how the conformational signals conveyed to the GTPase differ in the two cases.
Structural insights into cognate versus near-cognate discrimination during decoding., Agirrezabala X, Schreiner E, Trabuco LG, Lei J, Ortiz-Meoz RF, Schulten K, Green R, Frank J, EMBO J. 2011 Mar 4. PMID:21378755
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
- Ribosomal protein L1
- Ribosomal protein L2
- Ribosomal protein L3
- Ribosomal protein L4
- Ribosomal protein L5
- Ribosomal protein L6
- Ribosomal protein L9