Plays an important role in normal erythropoiesis (By similarity). It has a role in the differentiation of erythroid progenitors (By similarity). Regulates maturation and trafficking of the transmembrane metalloprotease ADAM10 (PubMed:26686862, PubMed:30463011). Negatively regulates ligand-induced Notch activity probably by regulating ADAM10 activity (PubMed:26686862). Mediates docking of ADAM10 to zonula adherens by interacting with ADAM10 and, in a PDZD11-dependent manner, with the zonula adherens protein PLEKHA7 (PubMed:30463011). Homodimer; disulfide-linked (PubMed:17158226). Interacts (via extracellular domain) with ADAM10 (via extracellular domain) (PubMed:26686862, PubMed:30463011). Interacts (via cytoplasmic domain) with PLEKHA7 (via WW domains); the interaction is dependent on PDZD11 being bound to PLEKHA7 and facilitates the docking of ADAM10 to zonula adherens (PubMed:30463011). Is localized to zonula adherens by PLEKHA7 by a PDZD11-dependent interaction. Predominantly expressed in erythroblasts. Belongs to the tetraspanin (TM4SF) family.