Figure 7.

Tat(44–61) selects a specific RNA structure. ¹H 1D NMR spectra of 21R⁺, a 21nt single stranded RNA, in the absence (black) or the presence (blue) of two equivalents of Tat(44–61) at different temperatures (indicated in gray at the right panel of the figure) were recorded. The chemical shifts of the aromatic protons did not overlap with the peptide chemical shifts and serve thus as an indicator for the peptide’s influence on the RNA conformation: the only visible peaks of the peptide in this spectral region are stemming from the aromatic protons of Y47 and are marked with asterisks. To follow changes in the spectrum upon addition of peptide gray dotted lines are added exemplarily, the symbol indicate if peaks are shifting upon addition of the peptide (less than and greater than symbol) or show no change (struck through circle).