Molecular mechanism of distinct chemokine engagement and functional divergence of the human Duffy antigen receptor

The Duffy antigen receptor, also known as FY glycoprotein or CD234, is a seven transmembrane (7TM) protein expressed primarily at the surface of red blood cells, and it displays strikingly promiscuous binding to multiple pro- and anti-inflammatory chemokines. Here, we comprehensively profile transducer-coupling for this receptor including G-proteins, GRKs, and β-arrestins to unequivocally establish its dramatic functional divergence, and discover potential non-canonical signaling pathways using a global phosphoproteomics analysis. we present a comprehensive profiling of transducer-coupling for this receptor using cell-based assays, and a global phosphoproteomics screen to identify novel, non-canonical downstream signaling pathways. We prepared samples under unstimulated and CCL7-stimulated conditions, generated proteolytic fragments by trypsin digestion, enriched for phosphorylated peptides using TiO2 beads, and then identified the phosphorylated peptides using liquid chromatography-tandem MS (LC-MS/MS).