Figure 7.
GRK6 forms a complex with PAR1 in activated platelets. (A) Lysates were prepared from resting or thrombin (1 U/mL) activated human platelets. Proteins were precipitated with an anti-PAR1 (ATAP-2) antibody or nonimmune immunoglobulin (Ig) and then probed for GRK6 before reprobing with an anti-PAR1 antibody (N = 5). Note that a marker lane was excised as indicated by the vertical line. (B) Lysates from human platelets incubated with thrombin (1 U/mL) were precipitated with (i) anti-PAR1 (ATAP-2) antibody, then probed with antiphosphoserine antibody before reprobing with an anti-PAR1 antibody, and (ii) antiphosphoserine antibody blot. (Bi) The graph summarizes 6 studies (mean ± SEM). (Bii) The graph summarizes 5 studies (mean ± SEM). (C) Lysates from WT or GRK6−/− MEG-01 were precipitated with anti-PAR1 antibody or nonimmune Ig and then probed with an antiphosphoserine antibody before reprobing with anti-PAR1 antibodies. The graph summarizes 3 studies (mean ± SEM) (Ci). (Cii) Lysates from WT or GRK6−/− MEG-01 were precipitated with antiphosphoserine antibody or nonimmune Ig. The graph summarizes 3 studies (mean ± SEM). (Ciii) Western blot confirmed the loss of GRK6 expression in GRK6−/− clones .