Download MendeleyTwo conformational states in the crystal structure of the Homo sapiens cytoplasmic ribosomal decoding A site.
Kondo, J., Urzhumtsev, A., Westhof, E.(2006) Nucleic Acids Res 34: 676-685
- PubMed: 16452297
- DOI: https://doi.org/10.1093/nar/gkj467
- Primary Citation of Related Structures:
2FQN - PubMed Abstract:
The decoding A site of the small ribosomal subunit is an RNA molecular switch, which monitors codon-anticodon interactions to guarantee translation fidelity. We have solved the crystal structure of an RNA fragment containing two Homo sapiens cytoplasmic A sites. Each of the two A sites presents a different conformational state. In one state, adenines A1492 and A1493 are fully bulged-out with C1409 forming a wobble-like pair to A1491. In the second state, adenines A1492 and A1493 form non-Watson-Crick pairs with C1409 and G1408, respectively while A1491 bulges out. The first state of the eukaryotic A site is, thus, basically the same as in the bacterial A site with bulging A1492 and A1493. It is the state used for recognition of the codon/anticodon complex. On the contrary, the second state of the H.sapiens cytoplasmic A site is drastically different from any of those observed for the bacterial A site without bulging A1492 and A1493.
Organizational Affiliation:
Institut de Biologie Moléculaire et Cellulaire, UPR9002 CNRS, Université Louis Pasteur, 15 rue René Descartes, 67084 Strasbourg, France.
