Fig. 4: Disruption of AIM cooperativity by 6G1 activates A1.

A Washed platelet aggregation in response to 1.5 mg/mL ristocetin (red), various concentrations of mAb 6G1 (pink), or anti-His-tag mAb (dark green) with 60 nM AIM-A1. Resting washed platelets are shown in light green. It should be noted the relative molarity for activation of 60 nM AIM-A1 is considerably lower for 6G1 compared to ristocetin, approximately 300 nM and 730 μM, respectively. B Representative force-extension traces of AIM-A1 alone (black) and AIM-A1 (pink), NAIM-A1 (blue), and A1-CAIM (red) in the presence of 30 µg/mL 6G1. The extension event in each trace is marked by an arrowhead. C Superimposed plots of unfolding force versus unfolding extension data and their fits to the worm-like chain model. Force data are presented as mean values ± standard deviation, and extension data are presented as the peak of the Gaussian fit ± the FWHM of Gaussian fit divided by the square root of counts. The data were obtained from n = 52, 58, 42, and 51 biologically independent single-molecule tethers for AIM-A1, AIM-A1 + 6G1, NAIM-A1 + 6G1, A1-CAIM + 6G1, respectively. D Regression of most probable unfolding forces fit the Bell–Evans model. Unfolding force data are presented as the center of the tallest bin of the histogram ± one-half of the bin width. The data were obtained from n = 52, 58, 42, and 51 biologically independent single-molecule tethers for AIM-A1, AIM-A1 + 6G1, NAIM-A1 + 6G1, A1-CAIM + 6G1, respectively. Source data for (C, D) are provided in two worksheets of the Source Data file.