Biochemical identification of A-minor motifs within RNA tertiary structure by interference analysis.

A-minor motifs are the most common tertiary structural elements in RNA helix packing. Biochemical identification of these interactions is now feasible using interference mapping analysis with the adenosine analogues 2'-deoxyadenosine and 3-deaza-adenosine. This approach was used to demonstrate that A-minor motifs mediate helix packing interactions that are important for 5'-splice site selection in the group I intron. By analysing the interference pattern of several analogues it is possible to identify and distinguish the four variants of the A-minor motif.