Cell-surface receptor that plays a role in cell-cell interactions, as well as cell adhesion and migration, helping them to sense and respond to changes in the tissue microenvironment. Participates thereby in a wide variety of cellular functions including the activation, recirculation and homing of T-lymphocytes, hematopoiesis, inflammation and response to bacterial infection. Engages, through its ectodomain, extracellular matrix components such as hyaluronan/HA, collagen, growth factors, cytokines or proteases and serves as a platform for signal transduction by assembling, via its cytoplasmic domain, protein complexes containing receptor kinases and membrane proteases. Such effectors include PKN2, the RhoGTPases RAC1 and RHOA, Rho-kinases and phospholipase C that coordinate signaling pathways promoting calcium mobilization and actin-mediated cytoskeleton reorganization essential for cell migration and adhesion. Interacts with PKN2 (By similarity). Interacts with TIAM1 and TIAM2 (By similarity). Interacts with HA, as well as other glycosaminoglycans, collagen, laminin, and fibronectin via its N-terminal segment. Interacts with UNC119. Interacts with PDPN (via extracellular domain); this interaction is required for PDPN-mediated directional migration and regulation of lamellipodia extension/stabilization during cell spreading and migration (By similarity). Interacts with RDX, EZR and MSN (By similarity). Interacts with EGFR (By similarity). Interacts with CD74; this complex is essential for the MIF-induced signaling cascade that results in B cell survival (By similarity). Colocalizes with actin in membrane protrusions at wounding edges. Co-localizes with RDX, EZR and MSN in microvilli. By EBV. The lectin-like LINK domain is responsible for hyaluronan binding. Phosphorylated; activation of PKC results in the dephosphorylation of Ser-326 (constitutive phosphorylation site), and the phosphorylation of Ser-292. N-glycosylated. O-glycosylated; addition of the glycosaminoglycan chondroitin sulfate, of sulfate, of phosphate to cytoplasmic domain serine residues.