@article{,
title = {Two conformational states in the crystal structure of the Homo sapiens cytoplasmic ribosomal decoding A site},
author = {J Kondo and A Urzhumtsev and E Westhof},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16452297},
isbn = {16452297},
year = {2006},
date = {2006-01-01},
journal = {Nucleic Acids Res},
volume = {34},
number = {2},
pages = {676-685},
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.},
note = {1362-4962 (Electronic)
Journal Article},
keywords = {16S/chemistry RNA, 18S/*chemistry Research Support, Animals Comparative Study Crystallography, Bacterial/chemistry RNA, Molecular Nebramycin/analogs & derivatives/chemistry Nucleic Acid Conformation RNA, Non-U.S. Gov't Ribosomes/chemistry Tetrahymena thermophila/genetics, Protozoan/chemistry RNA, Ribosomal, Unité ARN, WESTHOF, X-Ray Genetic Code Humans *Models},
pubstate = {published},
tppubtype = {article}
}
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.