Slow molecular recognition by RNA

Rate constants for ligands binding to structured RNAs (left column) and to proteins (middle column) and for RNA•protein association (right column). Values are presented in Supplemental Tables S1–S3, and “N” is the number of examples in each column. The upper dark gray box represents a generic diffusion limit centered around 10⁹ M⁻¹ sec⁻¹. In the box plot representations, the line inside the rectangle shows the median, the box spans the first quartile to the third quartile (representing the span from 0.25 to 0.75 of the ranked values), and the whiskers are shown as guides. The median values are as follows: RNA–ligand: 1.0 × 10⁵ M⁻¹ sec⁻¹; Protein–ligand: 6.6 × 10⁶ M⁻¹ sec⁻¹; and Protein–RNA: 6.3 × 10⁶ M⁻¹ sec⁻¹.