Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016632 (Fox)
 1,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Imino proton resonances in the downfield region (10-14 ppm) of the 500-MHz 1H NMR spectrum of Torulopsis utilis 5S RNA are identified (A X U, G X C, or G X U) and assigned to base pairs in helices I, IV, and V via analysis of homonuclear Overhauser enhancements (NOE) from intact T. utilis 5S RNA, its RNase T1 and RNase T2 digested fragments, and a second yeast (Saccharomyces cerevisiae) 5S RNA whose nucleotide sequence differs at only six residues from that of T. utilis 5S RNA. The near-identical chemical shifts and NOE behavior of most of the common peaks from these four RNAs strongly suggest that helices I, IV, and V retain the same conformation after RNase digestion and that both T. utilis and S. cerevisiae 5S RNAs share a common secondary and tertiary structure. Of the four G X U base pairs identified in the intact 5S RNA, two are assigned to the terminal stem (helix I) and the other two to helices IV and V. Seven of the nine base pairs of the terminal stem have been assigned. Our experimental demonstration of a G X U base pair in helix V supports the 5S RNA secondary structural model of Luehrsen and Fox [Luehrsen, K. R., & Fox, G.E. (1981) Proc. Natl. Acad. Sci. U.S.A. 78, 2150-2154]. Finally, the base-pair proton peak assigned to the terminal G X U in helix V of the RNase T2 cleaved fragment is shifted downfield from that in the intact 5S RNA, suggesting that helices I and V may be coaxial in intact T. utilis 5S RNA.
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PMID:Identification and assignment of base pairs in three helical stems of Torulopsis utilis ribosomal 5S RNA and its RNase T1 and RNase T2 cleaved fragments via 500-MHz proton homonuclear overhauser enhancements. 309 80

The structures of 5S ribosomal RNAs from Escherichia coli and Bacillus stearothermophilus were examined by using ribonucleases A, T1, and T2 and a double helix specific cobra venom ribonuclease. By using both 5' and 3'-32P-end labeling methods and selecting for digested but intact 5S RNA molecules, we were able to distinguish between primary and secondary cutting positions and also to establish the relative degree of cutting. The data reveal the predicted similarities of the higher order structure in the two RNAs but also demonstrate a few significant differences. The data also provide direct evidence for three of the helical regions of the Fox and Woese model of 5S RNA [Fox, G. E., & Woese, C. (1975) Nature (London) 256, 505] and support other important structural features which include a nucleotide looped out from a helical region which has been proposed as a recognition site for protein L18.
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PMID:Secondary structure of prokaryotic 5S ribosomal ribonucleic acids: a study with ribonucleases. 627 97