Receptor for TNFSF11/RANKL/TRANCE/OPGL; essential for RANKL-mediated osteoclastogenesis. Involved in the regulation of interactions between T-cells and dendritic cells. Binds to the clefts between the subunits of the TNFSF11 ligand trimer to form a heterohexamer. Interacts with TRAF1, TRAF2, TRAF3, TRAF5 and TRAF6 (By similarity). Interacts (via cytoplasmic domain) with GAB2 (By similarity). Ubiquitous expression with high levels in trabecular bone, thymus, small intestine, lung, brain and kidney. Weakly expressed in spleen and bone marrow.