The naturally occurring N6-threonyl adenine in anticodon loop of Schizosaccharomyces pombe tRNAi causes formation of a unique U-turn motif
Lescrinier, E., Nauwelaerts, K., Zanier, K., Poesen, K., Sattler, M., Herdewijn, P.(2006) Nucleic Acids Res 34: 2878-2886
- PubMed: 16738127 
- DOI: https://doi.org/10.1093/nar/gkl081
- Primary Citation of Related Structures:  
2G1G - PubMed Abstract: 
Modified nucleosides play an important role in structure and function of tRNA. We have determined the solution structure of the anticodon stem-loop (ASL) of initiator tRNA of Schizosaccharomyces pombe. The incorporation of N6-threonylcarbamoyladenosine at the position 3' to the anticodon triplet (t6A37) results in the formation of a U-turn motif and enhances stacking interactions within the loop and stem regions (i.e. between A35 and t6A37) by bulging out U36. This conformation was not observed in a crystal structure of tRNAi including the same modification in its anticodon loop, nor in the solution structure of the unmodified ASL. A t6A modification also occurs in the well studied anti-stem-loop of lys-tRNA(UUU). A comparison of this stem-loop with our structure demonstrates different effects of the modification depending on the loop sequence.
Organizational Affiliation: 
Laboratory of Medicinal Chemistry, Rega Institute for Medical Research BioMacs, K.U.Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium.