Abstract
Methyl and methylene protons of dihydrouridine 17 (hU), 6-methyladenosine 37 (M6A), 7-methylguanosine 46 (m7G), and ribothymidine 54 (rT) give clearly resolved peaks (220 MHz) for tRNA1val (coli solutions in D2O, 0.25 m NaCl, at 27 degrees C. Chemical shifts are generally consistent with a solution structure of tRNA1val similar to the crystal structure of tRNAphe (yeast). At least 3 separate transitions are observed as the temperature is raised. The earliest involves disruption of native tertiary structure and formation of intermediate structures in the m7G and rT regions. A second transition results in a change in structure of the anticodon loop, containing m6A. The final step involves unfolding of the m7G and rT intermediates and melting of the TpsiC helix. Low salt concentrations produce multiple, partially denatured conformations, rather than a unique form, for tRNA1val. Native structure is almost completely reformed by addition of Na+ but Mg2+ is required for correct conformation in the vicinity of m7G.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Cole P. E., Yang S. K., Crothers D. M. Conformational changes of transfer ribonucleic acid. Equilibrium phase diagrams. Biochemistry. 1972 Nov 7;11(23):4358–4368. doi: 10.1021/bi00773a024. [DOI] [PubMed] [Google Scholar]
- Daniel W. E., Jr, Cohn M. Changes in tertiary structure accompanying a single base change in transfer RNA. Proton magnetic resonance and aminoacylation studies of Escherichia coli tRNAMet f1 and tRNAMet f3 and their spin-labeled (s4U8) derivatives. Biochemistry. 1976 Sep 7;15(18):3917–3924. doi: 10.1021/bi00663a003. [DOI] [PubMed] [Google Scholar]
- Holmes W. M., Hurd R. E., Reid B. R., Rimerman R. A., Hatfield G. W. Separation of transfer ribonucleic acid by sepharose chromatography using reverse salt gradients. Proc Natl Acad Sci U S A. 1975 Mar;72(3):1068–1071. doi: 10.1073/pnas.72.3.1068. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kan L. S., Ts'o P. O., Sprinzl M., vd Harr F., Cramer F. 1H nuclear magnetic resonance studies of transfer RNA: the methyl and methylene resonances of baker's yeast phenylalanine transfer RNA and its fragments. Biochemistry. 1977 Jul 12;16(14):3143–3154. doi: 10.1021/bi00633a017. [DOI] [PubMed] [Google Scholar]
- Kastrup R. V., Schmidt P. G. 1H nuclear magnetic resonance of modified bases of valine transfer ribonucleic acid (Escherichia coli). A direct monitor of sequential thermal unfolding. Biochemistry. 1975 Aug 12;14(16):3612–3618. doi: 10.1021/bi00687a015. [DOI] [PubMed] [Google Scholar]
- Murao K., Saneyoshi M., Harada F., Nishimura S. Uridin-5-oxy acetic acid: a new minor constituent from E. coli valine transfer RNA I. Biochem Biophys Res Commun. 1970 Feb 20;38(4):657–662. doi: 10.1016/0006-291x(70)90631-5. [DOI] [PubMed] [Google Scholar]
- Pörschke D., Eigen M. Co-operative non-enzymic base recognition. 3. Kinetics of the helix-coil transition of the oligoribouridylic--oligoriboadenylic acid system and of oligoriboadenylic acid alone at acidic pH. J Mol Biol. 1971 Dec 14;62(2):361–381. doi: 10.1016/0022-2836(71)90433-5. [DOI] [PubMed] [Google Scholar]
- Quigley G. J., Rich A. Structural domains of transfer RNA molecules. Science. 1976 Nov 19;194(4267):796–806. doi: 10.1126/science.790568. [DOI] [PubMed] [Google Scholar]