Figure 4
From: On the mechanism of autoinhibition of the RhoA-specific nucleotide exchange factor PDZRhoGEF
The fragment containing residues 672–712, upstream of the DH-PH tandem, interacts with residues within the DH domain and with RhoA in the binary complex. (A) comparison of 900 MHz 1H-15N TROSY-HSQC spectra of DH-PH (blue) and PRG672–1081 (red) showing chemical shift changes within DH domain induced by the linker; only select fragments of the spectrum are shown for clarity (B) a graph showing the magnitude of linker induced chemical shift changes (ΔσHN [Hz]) within the DH domain (blue) compared to the surface area of DH residues buried upon formation of the complex with RhoA (red); ΔσHN [Hz] were calculated as a differences between chemical shifts for PRG672–1081and DH-PH; the surface buried upon complex formation was calculated using the crystal structure of DHPH-RhoA complex and the program MOLMOL [38]; (C) crystal structure of the DH-PH/RhoA complex (PDB code 1XCG), showing the residues within the DH domain with the largest amide chemical shift changes induced by the linker (>50 Hz, red; 25 – 50 Hz, orange); the hypothetical position of the linker, postulated on the basis of chemical shift perturbations, is shown in yellow; side chains of acidic residues within the linker are shown in space filling representation; RhoA is shown as blue ribbon; (D) comparison of 600 MHz 1H-15N TROSY-HSQC spectra of RhoA in complex with DH-PH (blue) and PRG672–1081 (red); several RhoA amides with chemical shifts perturbed by the presence of the linker are circled.