FIGURE 3.

Spin relaxation-based comparison of the E-wtTAR and E-TAR_m conformational dynamics. (a) Elongated construct of wtTAR in which XY are unlabeled CG (E-GC-wtTAR) and UA (and E-AU-wtTAR) residues as previously described (29). Residues that undergo significant chemical shift perturbations upon elongation are highlighted on the secondary structure using black solid symbols. See inset in Fig. 1 d for symbol key. (b) 2D HSQC spectra of wtTAR (red) overlaid on corresponding spectra of E-AU-wtTAR and E-GC-wtTAR (black). Blue labels denote loop resonances that shift upon elongation. (c) Correlation plot between the E-wtTAR and E-TAR_m normalized intensities. Shown is the correlation coefficient (R). (d) Normalized resonance intensities (peak heights) measured from 2D HSQC spectra of E-wtTAR. See inset for key. (e) Correlation plot between nucleobase carbon values measured in nonelongated wtTAR and TAR_m. Values for domain I, bulge, and domain II are shown in red, orange, and green circles, respectively.