The solution structure of ribosomal protein L18 from Thermus thermophilus reveals a conserved RNA-binding fold.
Woestenenk, E.A., Gongadze, G.M., Shcherbakov, D.V., Rak, A.V., Garber, M.B., Hard, T., Berglund, H.(2002) Biochem J 363: 553-561
- PubMed: 11964156 
- DOI: https://doi.org/10.1042/0264-6021:3630553
- Primary Citation of Related Structures:  
1ILY - PubMed Abstract: 
We have determined the solution structure of ribosomal protein L18 from Thermus thermophilus. L18 is a 12.5 kDa protein of the large subunit of the ribosome and binds to both 5 S and 23 S rRNA. In the uncomplexed state L18 folds to a mixed alpha/beta globular structure with a long disordered N-terminal region. We compared our high-resolution structure with RNA-complexed L18 from Haloarcula marismortui and T. thermophilus to examine RNA-induced as well as species-dependent structural differences. We also identified T. thermophilus S11 as a structural homologue and found that the structures of the RNA-recognition sites are conserved. Important features, for instance a bulge in the RNA-contacting beta-sheet, are conserved in both proteins. We suggest that the L18 fold recognizes a specific RNA motif and that the resulting RNA-protein-recognition module is tolerant to variations in sequence.
Organizational Affiliation: 
Royal Institute of Technology (KTH), SCFAB, Department of Biotechnology, S-106 91 Stockholm, Sweden.