Ligand-modulated folding of the full-length adenine riboswitch probed by NMR and single-molecule FRET spectroscopy.

ABSTRACT: The full-length translation-regulating add adenine riboswitch (Asw) from Vibrio vulnificus has a more complex conformational space than its isolated aptamer domain. In addition to the predicted apo (apoA) and holo conformation that feature the conserved three-way junctional purine riboswitch aptamer, it adopts a second apo (apoB) conformation with a fundamentally different secondary structure. Here, we characterized the ligand-dependent conformational dynamics of the full-length add Asw by NMR and by single-molecule FRET (smFRET) spectroscopy. Both methods revealed an adenine-induced secondary structure switch from the apoB-form to the apoA-form that involves no tertiary structural interactions between aptamer and expression platform. This strongly suggests that the add Asw triggers transl

SUBMITTER: Warhaut S 

PROVIDER: S-EPMC5605240 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature