Download MendeleyThe Plasticity of a Structural Motif in RNA: Structural Polymorphism of a Kink Turn as a Function of its Environment.
Daldrop, P., Lilley, D.M.J.(2013) RNA 19: 357
- PubMed: 23325110
- DOI: https://doi.org/10.1261/rna.036657.112
- Primary Citation of Related Structures:
4B5R - PubMed Abstract:
The k-turn is a widespread structural motif that introduces a tight kink into the helical axis of double-stranded RNA. The adenine bases of consecutive G•A pairs are directed toward the minor groove of the opposing helix, hydrogen bonding in a typical A-minor interaction. We show here that the available structures of k-turns divide into two classes, depending on whether N3 or N1 of the adenine at the 2b position accepts a hydrogen bond from the O2' at the -1n position. There is a coordinated structural change involving a number of hydrogen bonds between the two classes. We show here that Kt-7 can adopt either the N3 or N1 structures depending on environment. While it has the N1 structure in the ribosome, on engineering it into the SAM-I riboswitch, it changes to the N3 structure, resulting in a significant alteration in the trajectory of the helical arms.
Organizational Affiliation:
Cancer Research UK Nucleic Acid Structure Research Group, MSI/WTB Complex, The University of Dundee, Dundee DD1 5EH, United Kingdom.
