Extended Data Fig. 7: Sgt2C’s autoinhibition does not involve direct interaction with Sgt2N.
From: Remote on–off switching of protein activity by intrinsically disordered region
a, Overlay of 1H-15N-HSQC spectra of Sgt2C in the absence (gray) and presence (blue, outer contours only) of a 1:1 ratio of unlabeled Sgt2NT. Sgt2NT is calculated as a dimer, and Sgt2C as a monomer. The excellent spectral overlap indicates no direct interaction. b,c, Residue-resolved NMR signal attenuation (I/I0) of 15N-labeled Sgt2NT (b) and Sgt2C (c) upon titration with unlabeled Sgt2C and Sgt2NT, respectively. I0 and I represent signal intensities before and after titration. Minimal intensity changes in both cases confirm the absence of direct interaction between Sgt2NT and Sgt2C. d, ITC analysis of MTSL spin-labeled Sgt2 C39S/S294C with Get4/5, showing no interaction. Spin-labeled Sgt2 is calculated as a dimer, and Get4/5 as a heterotetramer. This result indicates that MTSL attachment does not interfere with the autoinhibitory activity of Sgt2C. e,f, Overlay of methyl-TROSY spectra of spin-labeled Sgt2 at residue 254 (e, red) and 294 (f, purple) in the paramagnetic state, compared with the corresponding spectra in the diamagnetic state (grey, bottom). The associated intensity plots are shown in Fig. 4d. The observed PRE effects are minimal, except for neighboring residue.
