SORL1 is likely to be a multifunctional endocytic receptor, that may be implicated in the uptake of lipoproteins and of proteases. It binds LDL, the major cholesterol-carrying lipoprotein of plasma, and transports it into cells by endocytosis. SORL1 binds the receptor-associated protein (RAP). It could play a role in cell-cell interaction. SORL1 is expressed mainly in brain, where it is most abundant in the cerebellum, cerebral cortex and the occipital pole; low expression in the putamen and the thalamus. It is also found in spinal cord, testis, liver, kidney and pancreas with detectable levels in placenta, lung and heart. Moreover, it is expressed in the prostate, ovary, thyroid and spleen, but not found in kidney, liver, lung, skeletal muscle, bone marrow and adrenals.