Schematic showing the role of TRPML1 in vesicular trafficking. TRPML1 is active in the membrane of late-endosomes and facilitates fusion of these vesicles with lysosomes or the plasma membrane. Channels delivered to the plasma membrane are redelivered to the late-endosomes via endocytosis. Whereas delivery of vesicles to the lysosomes is required for cholesterol de-esterification in that compartment, vesicular fusion with the plasma membrane is required for cholesterol recycling. 