Hydration dependent dynamics in RNA

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Hydration dependent dynamics in RNA


Abstract The essential role played by local and collective motions in RNA function has led to a growing interest in the characterization of RNA dynamics. Recent investigations have revealed that even relatively simple RNAs experience complex motions over multiple time scales covering the entire msâ??ps motional range. In this work, we use deuterium solid-state NMR to systematically investigate motions in HIV-1 TAR RNA as a function of hydration. We probe dynamics at three uridine residues in different structural environments ranging from helical to completely unrestrained. We observe distinct and substantial changes in 2H solid-state relaxation times and lineshapes at each site as hydration levels increase. By comparing solid-state and solution state 13C relaxation measurements, we establish that nsâ??μs motions that may be indicative of collective dynamics suddenly arise in the RNA as hydration reaches a critical point coincident with the onset of bulk hydration. Beyond that point, we observe smaller changes in relaxation rates and lineshapes in these highly hydrated solid samples, compared to the dramatic activation of motion occurring at moderate hydration.

• Content Type Journal Article
• Pages 133-142
• DOI 10.1007/s10858-009-9355-6
• Authors
  • Greg L. Olsen, University of Washington Department of Chemistry Box 351700 Seattle WA 98195 USA
  • Michael F. Bardaro, University of Washington Department of Chemistry Box 351700 Seattle WA 98195 USA
  • Dorothy C. Echodu, University of Washington Department of Chemistry Box 351700 Seattle WA 98195 USA
  • Gary P. Drobny, University of Washington Department of Chemistry Box 351700 Seattle WA 98195 USA
  • Gabriele Varani, University of Washington Department of Chemistry Box 351700 Seattle WA 98195 USA

• • Journal Journal of Biomolecular NMR
  • Online ISSN 1573-5001
  • Print ISSN 0925-2738
  • Journal Volume Volume 45
  • Journal Issue Volume 45, Numbers 1-2

Source: Journal of Biomolecular NMR