1ajl
|
FIVE-NUCLEOTIDE BULGE LOOP FROM TETRAHYMENA THERMOPHILA GROUP I INTRON
OverviewOverview
We present the solution conformation, determined by NMR spectroscopy, of a, five-nucleotide RNA bulge loop. The bulge interrupts the stem of a, 25-nucleotide RNA hairpin, and its sequence and flanking sequences are, those of a conserved bulge from a Group I intron. The secondary structure, of the bulge loop in the hairpin context is that predicted by the, secondary structure prediction algorithm of Zuker. It differs, however, from the secondary structure deduced from sequence covariation of the, bulge in the context of the functionally folded Group I introns and, observed in the crystal structure of an independently folding domain of, the Group I intron from Tetrahymena thermophila. This difference, represents an exception to the heierarchical model of RNA folding in which, preformed elements of secondary structure interact to form a tertiary, structure. The three-dimensional structure of the bulge loop is, characterized by discontinuous base stacking. Adjacent adenines stack with, each other and with the flanking double helices. However, the position of, the central uracil is not well defined by NOE distance constraints and is, a point of discontinuity in the base stacking.
About this StructureAbout this Structure
1AJL is a Protein complex structure of sequences from Tetrahymena thermophila. Full crystallographic information is available from OCA.
ReferenceReference
Solution conformation of a five-nucleotide RNA bulge loop from a group I intron., Luebke KJ, Landry SM, Tinoco I Jr, Biochemistry. 1997 Aug 19;36(33):10246-55. PMID:9254623
Page seeded by OCA on Sat Nov 24 22:57:23 2007