Figure 5.

NMR titrations of SUMO-3 and PIASy(409–501) containing both original and new SIMs. A, schematic of PIASy indicating fragment 409–501 containing both the original SIM and the new SIM used in the experiment. B, 2D ¹H-¹⁵N HSQC spectra of ¹⁵N-labeled SUMO-3 titrated with increasing amounts of PIASy(409–501). Expanded sections of representative SUMO-3 residues affected by the binding of PIASy(409–501) are on the right. C, plot of relative peak intensity for SUMO-3 resonances in the ligand-bound versus -free form (I_1:0.25/I_1:0). Gray and red lines depict mean and one standard deviation from the mean (1σ), respectively. D, the SUMO-3 residues affected upon complex formation with PIASy(409–501) are highlighted (red, residues displaying significant peak intensity reduction; orange, residues with significant change in the peak position). Error bars represent S.D.