1k6g
From Proteopedia
Solution Structure of Conserved AGNN Tetraloops: Insights into Rnt1p RNA Processing
Overview
Rnt1p, the yeast orthologue of RNase III, cleaves rRNAs, snRNAs and snoRNAs at a stem capped with conserved AGNN tetraloop. Here we show that 9 bp long stems ending with AGAA or AGUC tetraloops bind to Rnt1p and direct specific but sequence-independent RNA cleavage when provided with stems longer than 13 bp. The solution structures of these two tetraloops reveal a common fold for the terminal loop stabilized by non-canonical A-A or A-C pairs and extensive base stacking. The conserved nucleotides are stacked at the 5' side of the loop, exposing their Watson-Crick and Hoogsteen faces for recognition by Rnt1p. These results indicate that yeast RNase III recognizes the fold of a conserved single-stranded tetraloop to direct specific dsRNA cleavage.
About this Structure
Full crystallographic information is available from OCA.
Reference
Solution structure of conserved AGNN tetraloops: insights into Rnt1p RNA processing., Lebars I, Lamontagne B, Yoshizawa S, Aboul-Elela S, Fourmy D, EMBO J. 2001 Dec 17;20(24):7250-8. PMID:11743001 Page seeded by OCA on Fri May 2 22:21:53 2008
