Effect of methylation of adenine N6on kink turn structure depends on location.Ashraf, S., Huang, L., Lilley, D.M.J.
(2019) RNA Biol 16: 1377-1385
- PubMed: 31234702
- DOI: https://doi.org/10.1080/15476286.2019.1630797
- Primary Citation of Related Structures:
- PubMed Abstract:
N 6 -methyladenine is the most common covalent modification in cellular RNA species, with demonstrated functional consequences. At the molecular level this methylation could alter local RNA structure, and/or modulate the binding of specific proteins. We have previously shown that trans -Hoogsteen-sugar (sheared) A:G base pairs can be completely disrupted by methylation, and that this occurs in a sub-set ofD/D k-turn structures. In this work we have investigated to what extent sequence context affects the severity with which inclusion of N 6 -methyladenine into different A:G base pairs of a standard k-turn affects RNA folding and L7Ae protein binding. We find that local sequence has a major influence, ranging from complete absence of folding and protein binding to a relatively mild effect. We have determined the crystal structure of one of these species both free and protein-bound, showing the environment of the methyl group and the way the modification is accommodated into the k-turn structure.
Cancer Research UK Nucleic Acid Structure Research Group, MSI/WTB Complex, The University of Dundee , Dundee , U.K.