Fig. 5.

Experimentally-measured dynamics of N-SH2 and C-SH2 in the apo state and in complex with ITIM and ITSM. (A) Amide-specific entropy changes measured between apo N-SH2 and the N-SH2–ITIM complex (left), apo N-SH2 and the N-SH2–ITSM complex (centre), apo C-SH2 and the C-SH2–ITSM complex (right). An entropy increase/decrease is represented by a red/cyan sphere. The entropy changes were calculated from the Lipari-Szabo amide order-parameters and are due to internal dynamics on the ps timescale. (B) Differences in the hydrogen-bond network of the BG loop in the N-SH2–ITIM and N-SH2–ITSM complexes. (C) Transverse-relaxation exchange-broadening contributions due to slow dynamics ${(R}_{2,\mathrm{ex}}^{\ast })$as measured by CPMG relaxation dispersion for N-SH2 (panel C1: apo state, and in complex with ITIM and ITSM peptides) and C-SH2 (panel C2: apo and in complex with ITSM peptide). Amide nitrogens with significant exchange-broadening are shown as spheres, and are colored yellow, orange and red in order of increasing $R_{2,\mathrm{ex}}^{\ast }$ (according to the thresholds shown in the plots of supplementary figures S3 & S4). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)