Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1969 Oct;64(2):731–738. doi: 10.1073/pnas.64.2.731

PHOTOHYDRATION OF URIDINE IN THE RNA OF COLIPHAGE R17, I. REDUCTIVE ASSAY FOR URIDINE PHOTOHYDRATION*

P A Cerutti 1, N Miller 1, M G Pleiss 1,†, J F Remsen 1, W J Ramsay 1
PMCID: PMC223405  PMID: 5261044

Abstract

Photohydration of uridine in the RNA of E. coli bacteriophage R17 has been investigated with the help of a new chemical method which avoids digestion of the irradiated polymer. The uridine photohydrates are reductively cleaved with sodium borotritiide and the radioactively labeled fragment, 1,3-propane-diol-3Hα, 3Hα, 3Hγ, formed in this reaction is isolated and used as a measure for the extent of uridine photohydration in the irradiated RNA.

The influence of the conformational state of R17-RNA on the cross section of uridine photohydration (σH) was investigated. The cross section for irradiation at 280 mμ at 25° was largest in 6 M urea (σH = 0.053), slightly smaller in low salt (<10-3M Na+; σH = 0.050), and substantially smaller in 0.15 M Na+ (σH = 0.038). The closeness of the values for σH in urea and low salt indicates that a majority of the uridine residues in R17-RNA in the low salt medium at 25° are not hydrogen bonded and destacked. The significant suppression of photohydration in 0.15 M Na+ on the other hand shows that a substantial portion of the uridine residues in R17-RNA are participating in base pairing and base stacking under these conditions. Our results demonstrate that studies of uridine photohydration may, beyond their importance to photobiology, yield information specifically about the conformational state of the uridine-rich regions of a RNA, information which cannot be readily obtained by other techniques.

Full text

PDF
731

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Brahms J., Maurizot J. C., Michelson A. M. Conformational stability of dinucleotides in solution. J Mol Biol. 1967 May 14;25(3):481–495. doi: 10.1016/0022-2836(67)90200-8. [DOI] [PubMed] [Google Scholar]
  2. Cerutti P., Holt J. W., Miller N. Detection and determination of 5,6-dihydrouridine and 4-thiouridine in transfer ribonucleic acid from different sources. J Mol Biol. 1968 Jun 28;34(3):505–518. doi: 10.1016/0022-2836(68)90176-9. [DOI] [PubMed] [Google Scholar]
  3. Cerutti P., Kondo Y., Landis W. R., Witkop B. Photoreduction of uridine and reduction of dihydrouridine with sodium borohydride. J Am Chem Soc. 1968 Jan 31;90(3):771–775. doi: 10.1021/ja01005a039. [DOI] [PubMed] [Google Scholar]
  4. Cerutti P., Miller N. Selective reduction of yeast transfer ribonucleic acid with sodium borohydride. J Mol Biol. 1967 May 28;26(1):55–66. doi: 10.1016/0022-2836(67)90260-4. [DOI] [PubMed] [Google Scholar]
  5. GESTELAND R. F., BOEDTKER H. SOME PHYSICAL PROPERTIES OF BACTERIOPHAGE R17 AND ITS RIBONUCLEIC ACID. J Mol Biol. 1964 Apr;8:496–507. doi: 10.1016/s0022-2836(64)80007-3. [DOI] [PubMed] [Google Scholar]
  6. JOHNS H. E., PEARSON M. L., LEBLANC J. C., HELLEINER C. W. THE ULTRAVIOLET PHOTOCHEMISTRY OF THYMIDYLYL-(3'-5')-THYMIDINE. J Mol Biol. 1964 Aug;9:503–524. doi: 10.1016/s0022-2836(64)80223-0. [DOI] [PubMed] [Google Scholar]
  7. Kondo Y., Witkop B. Reductive ring openings of glutarimides and barbiturates with sodium borohydride. J Org Chem. 1968 Jan;33(1):206–212. doi: 10.1021/jo01265a039. [DOI] [PubMed] [Google Scholar]
  8. Kunieda T., Grossman L., Witkop B. Incorporation of tritium into irradiated nucleotides. Biochem Biophys Res Commun. 1968 Nov 8;33(3):453–456. doi: 10.1016/0006-291x(68)90594-9. [DOI] [PubMed] [Google Scholar]
  9. Kunieda T., Witkop B. Hydrogenolysis of thymien dimer to cyclobutanes by sodium borohydride. J Am Chem Soc. 1967 Aug 2;89(16):4232–4233. [PubMed] [Google Scholar]
  10. Miller N., Cerutti P. Structure of the photohydration products of cytidine and uridine. Proc Natl Acad Sci U S A. 1968 Jan;59(1):34–38. doi: 10.1073/pnas.59.1.34. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Mitra S., Enger M. D., Kaesberg P. PHYSICAL AND CHEMICAL PROPERTIES OF RNA FROM THE BACTERIAL VIRUS R17. Proc Natl Acad Sci U S A. 1963 Jul;50(1):68–75. doi: 10.1073/pnas.50.1.68. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Small G. D., Tao M., Gordon M. P. Pyrimidine hydrates and dimers in ultraviolet-irradiated tobacco mosaic virus ribonucleic acid. J Mol Biol. 1968 Nov 28;38(1):75–87. doi: 10.1016/0022-2836(68)90129-0. [DOI] [PubMed] [Google Scholar]
  13. de Boer G., Pearson M., Johns H. E. Ultraviolet photoproducts in ordered structures of poly U and their effects on secondary structure. J Mol Biol. 1967 Jul 14;27(1):131–144. doi: 10.1016/0022-2836(67)90356-7. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES