Fig. 7.

GRK5/6 knockdown differentially attenuates βarrestin2 recruitment. (A) Illustration of CXCR3 truncation C-terminal mutants. (B) Truncation of either CXCR3A or CXCR3B reduced βarr2 recruitment as measured by BRET in response to CXCL11 (500 nM). (C) siRNA knockdown of either GRK2/3 or GRK5/6 reduced CXCL11(500 nM) induced βarr2 recruitment to CXCR3A; however, as shown in (D) only siRNA knockdown of GRK2/3, but not GRK5/6, reduced βarr2 recruitment to CXCR3B. In (B), *P < 0.05 by unpaired student’s t test between respective WT and truncation mutant; in (C) and (D), *P < 0.05 by one-way analysis of variance with Tukey’s post hoc comparison between all treatment groups. n ≥ 3 biologic replicates per condition.