Fig. 3: Binding of myrArf1 to ASAP1 PH at the membrane.
From: An active allosteric mechanism in ASAP1-mediated Arf1 GTP hydrolysis redefines PH domain function
A 1H-13C (top) and 1H-15N CSPs (bottom) observed between ASAP1 PH bound to ND only or ND in the presence of myrArf1 (PH:Arf1 1:1.2) plotted against residue number. The error bars were calculated based on the digital resolution of the spectra, as described in “Methods”. B CSP values are mapped on the Arf1 surface: CSP > 2σ (red), CSP > 1σ (orange). In addition to the large CSPs observed on the β sandwich, the large CSP observed for Ile353 (β1/β2 loop) could result from a reorientation of wt PH at the membrane in the presence of myrArf1 or from a direct interaction with myrArf1. Images created using Chimera56. C Intermolecular PRE profile measured on 13C methyl labeled ASAP1 PH in the presence of MTSL-tagged myrArf1K38C at the membrane surface. Two independent experiments were performed. All data points are plotted as open or filled circles. Error bars were calculated based on the signal-to-noise (S/N) ratio of the spectra as described in Methods. D PRE < 0.2 in the presence of MTSL-tagged myrArf1K38C mapped on the ASAP1 structure. Two patches were observed on opposite side of the β sandwich: The first patch includes residues Val390 (β5 strand), Ala394 (β5/β6 loop), Leu402, Ile403 ((β6 strand) and Ala413 on β7 strand (called hereafter β5/β7 patch). The second patch includes residues Ile368 and Thr370 on the β3 strand (called thereafter β2/β3 patch). Images created using Chimera56. Source data are provided as a Source data file.
