Role of megalin and cubilin in renal physiology and pathophysiology.
Megalin and cubilin are endocytic receptors highly expressed in the endocytic apparatus of the renal proximal tubule. These receptors appear to be responsible for the tubular clearance of most proteins filtered in the glomeruli. Cubilin is a peripheral membrane protein, and therefore it does not have an endocytosis signaling sequence. It appears that megalin is responsible for internalization of cubilin and its ligands in addition to internalizing its own ligands. The proteinuria observed in megalin-deficient mice, in dogs lacking functional cubilin, and in patients with distinct mutations of the cubilin gene illustrates the importance of the receptors.
Christensen
E I
EI
University of Aarhus, Department of Cell Biology, Institute of Anatomy, University Park, Building 234, 8000 Aarhus C, Denmark. eic@ana.au.dk
Nielsen
R
R
D000818:Animals; D004705:Endocytosis; D006801:Humans; D007668:Kidney / Q000502:physiology* / Q000503:physiopathology; D007674:Kidney Diseases / Q000473:pathology / Q000503:physiopathology*; D007678:Kidney Glomerulus / Q000502:physiology; D026561:Low Density Lipoprotein Receptor-Related Protein-2 / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000502:physiology; D011956:Receptors, Cell Surface / Q000502:physiology*
D026561:Low Density Lipoprotein Receptor-Related Protein-2; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; C029486:intrinsic factor-cobalamin receptor