Authors: | Al-Hashimi, H.; Pitt, S. W.; Majumdar, A.; Xu, W.; Patel, D. J. |
Article Title: | Mg2+-induced variations in the conformation and dynamics of HIV-1 TAR RNA probed using NMR residual dipolar couplings |
Abstract: | The effects of divalent Mg2+ on the conformation and dynamics of the stem-loop transactivation response element (TAR) RNA from HIV-1 have been characterized using NMR residual dipolar couplings (RDCs). Order matrix analysis of one bond 13C-1H RDCs measured in TAR at [Mg2+]:[TAR] stoichiometric ratios of ∼3:1 (TAR(3.0Mg)) and ∼4.5:1 (TAR(4.5Mg)) revealed that Mg2+ reduces the average inter-helical angle from 47(±5)° in TAR(free) to 5(±7)° in TAR(4.5Mg). In contrast to the TAR(free) state, the generalized degree of order for the two stems in TAR(4.5Mg) is found to be identical within experimental uncertainty, indicating that binding of Mg2+ leads to an arrest of inter-helical motions in TAR(free). Results demonstrate that RDC-NMR methodology can provide new insight into the effects of Mg2+ on both the conformation and dynamics of RNA. © 2003 Elsevier Science Ltd. All rights reserved. |
Keywords: | genetics; nonhuman; methodology; metabolism; chemistry; virus rna; nucleic acids; magnetic resonance spectroscopy; nuclear magnetic resonance spectroscopy; hydrogen bond; models, molecular; solutions; chemical structure; conformation; nucleic acid conformation; rna structure; dna helix; dna responsive element; solution and solubility; rna, viral; human immunodeficiency virus 1; hiv-1; stoichiometry; long terminal repeat; magnesium; hiv long terminal repeat; rna folding; priority journal; article; collective motions; divalent metal ions; transactivation response element; transactivation responsive element |
Journal Title: | Journal of Molecular Biology |
Volume: | 329 |
Issue: | 5 |
ISSN: | 0022-2836 |
Publisher: | Academic Press Inc., Elsevier Science |
Date Published: | 2003-06-20 |
Start Page: | 867 |
End Page: | 873 |
Language: | English |
DOI: | 10.1016/s0022-2836(03)00517-5 |
PUBMED: | 12798678 |
PROVIDER: | scopus |
PMCID: | PMC4692374 |
DOI/URL: | |
Notes: | Export Date: 12 September 2014 -- Source: Scopus |