Fig. 5.

Megalin takes up albumin independently of cubilin in nephrotic podocin knockout (KO) mice. A−F: immunostaining for cubilin (red), megalin (blue), and albumin (green) in kidney sections from control mice (A), inducible cubilin KO mice (B), inducible megalin KO mice (C), inducible podocin KO mice (D), inducible podocin/cubilin KO mice (E), and inducible podocin/megalin KO mice (F). Confocal images were taken at ×20 magnification. Scale bars = 40 μm. Only megalin- and cubilin-positive cells take up albumin in normal mice; under proteinuria, cubilin expression is dispensable for albumin uptake (but megalin is not).