Endocytic receptor which plays a role in lipoprotein, vitamin and iron metabolism by facilitating their uptake (  ). Acts together with LRP2 to mediate endocytosis of high-density lipoproteins, GC, hemoglobin, ALB, TF and SCGB1A1. Acts together with AMN to mediate endocytosis of the CBLIF-cobalamin complex (, ). Binds to ALB, MB, Kappa and lambda-light chains, TF, hemoglobin, GC, SCGB1A1, APOA1, high density lipoprotein, and the CBLIF-cobalamin complex. Ligand binding requires calcium . Serves as important transporter in several absorptive epithelia, including intestine, renal proximal tubules and embryonic yolk sac. May play an important role in the development of the peri-implantation embryo through internalization of APOA1 and cholesterol. Binds to LGALS3 at the maternal-fetal interface.
Subcellular locations: Apical cell membrane, Cell membrane, Membrane, Coated pit, Endosome, Lysosome membrane
Lacks a transmembrane domain and depends on interaction with AMN for location at the plasma membrane (, ). Colocalizes with AMN and LRP2 in the endocytotic apparatus of epithelial cells (By similarity).
Detected in kidney cortex (at protein level) . Expressed in kidney proximal tubule cells, placenta, visceral yolk-sac cells and in absorptive intestinal cells. Expressed in the epithelium of intestine and kidney.