Probing the conformation of human tRNA3Lys in solution by NMR

Human tRNA3Lys acts as a primer for the reverse transcription of human immunodeficiency virus genomic RNA. To form an initiation complex with genomic RNA, tRNA3Lys must reorganize its secondary structure. To provide a starting point for mechanistic studies of the formation of the initiation complex, we here present solution NMR investigations of human tRNA3Lys. We use a straightforward set of NMR experiments to show that tRNA3Lys adopts a standard transfer ribonucleic acid tertiary structure in solution, and that Mg2+ is required for this folding. The results underscore the power of NMR to reveal rapidly the conformation of RNAs.