Figure 3. Activation of CXCR7-β-arrestin 2 interaction by peptides.
MDA-MB-231 breast cancer cells expressing a click beetle luciferase complementation reporter for CXCR7 interaction with β-arrestin 2 were incubated with 300 ng/ml CXCL12, 300 μM 17-mer peptide, or vehicle control. We acquired bioluminescence images every 3 minutes for 45 minutes. Graph shows mean values ± SEM for fold increase in bioluminescence relative to cells treated with vehicle control (n = 4 per condition). **, p < 0.01; and *, p < 0.05 relative to vehicle control.