Open AccessHigher order structural elements in ribosomal RNAs: pseudo-knots and the use of noncanonical pairs.
Author(s) -
Robin R. Gutell,
Carl R. Woese
Publication year - 1990
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.87.2.663
Subject(s) - ribosomal rna , biology , protein subunit , protein secondary structure , eukaryotic large ribosomal subunit , computational biology , plastid , genetics , base pair , order (exchange) , evolutionary biology , 18s ribosomal rna , dna , biochemistry , gene , chloroplast , finance , economics
The data base of prokaryotic small subunit ribosomal RNAs alone now numbers more than 400 sequences, while that for the large subunit rRNAs numbers more than 70 when eukaryotic, mitochondrial, and plastid sequences are also included. Comparisons among these rRNA sequences reveal a number of positions that covary in composition, suggestive of higher order structural elements; 5 such structures are reported for the small subunit rRNA and 15 for the large subunit rRNA. While some of these are properly (small) secondary structural elements, the majority would have to be classified as more complex "tertiary" interactions, which in some cases bring together diverse areas in the secondary structural diagram. A number of the covariances are not of the canonical type, indicating non-Watson-Crick interactions.