Involvement of a GNRA tetraloop in long-range RNA tertiary interactions.
Terminal loops with a GNRA consensus sequence are widespread in RNA. It has been suggested that these loops act as "anchors" during tertiary folding, by interacting in a sequence-specific way with helices at distant locations along the molecule. We now show that a GUGA loop changes state upon disruption of the tertiary architecture of a self-splicing group I intron. Successful replacement of the postulated loop-helix contact by classical base-pairing points to binding of the loop into the shallow (minor) groove of the helix, as also indicated by partial restoration of ribozyme stability upon a specific double nucleotide substitution.
Jaeger
L
L
Centre de Génétique Moléculaire du C.N.R.S., Gif-sur-Yvette, France.
Michel
F
F
Westhof
E
E
D017122:Bacteriophage T4; D001483:Base Sequence; D006860:Hydrogen Bonding; D007438:Introns; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012313:RNA / Q000737:chemistry*; D012367:RNA, Viral / Q000737:chemistry
D012367:RNA, Viral; D012313:RNA