Figure 5.

CCR7 G protein activation, β-arrestin recruitment, and internalization induced by CCL19, CCL21, and tailless-CCL21. (A) Dose–response curves of CCL19 (circles), CCL21 (squares), and tailless-CCL21 (triangles) obtained in PI-turnover assay measured in HEK293 cells cotransfected with CCR7 and the chimeric G protein G_qi4myr. Statistical significant difference from CCL19 was calculated by unpaired Student’s t-test. *P < 0.05, **P < 0.01, and NS, not significant. (B) β-arrestin recruitment measured in U2OS cells stably transfected with β-arrestin 2 linked to an enzyme acceptor and transiently transfected with enzyme donor-fused CCR7 with increasing concentrations of CCL19 (circles), CCL21 (squares), and tailless-CCL21 (triangles). Statistical significance between CCL19 and CCL21 values was calculated using unpaired t test. **P < 0.01. (C) β-Arrestin 2-dependent internalization measured in U2OS cells coexpressing untagged CCR7 DNA, β-arrestin 2 fused to the enzyme acceptor part of β-gal, and endosomes tagged with PK, the enzyme donor. Dose–response curves for CCL19 (circles) and CCL21 (squares) are shown. Statistical significance was calculated using unpaired t test (n = 3–4).