Figure 1.

Chemical structures and reactions of structure-specific probes used to interrogate RNA structure. a) DMS reactions that measure adenosine and cytosine single-stranded positions. b) Kethoxal reaction that measures single-stranded guanosine positions. c) Carbodiimide chemical reactions used to identify single-stranded uridine positions in RNA. d) SHAPE carbonyl electrophiles for interrogating flexible positions. e) NAz aroyl azide, when exposed to light, reacts with solvent exposed C-8 guanosine and adenosine residues in RNA.