NPC intracellular cholesterol transporter 2 (NPC2)

Intracellular cholesterol transporter which functions in concert with NPC1 and plays an important role in the egress of cholesterol from the endosomal/lysosomal compartment. Both NPC1 and NPC2 function as the mobile'tag team duo' (TTD) to catalyze the mobilization of cholesterol within the multivesicular environment of the late endosome (LE) to influence egress through the limiting bilayer of the LE.

NPC2 binds unesterified cholesterol that has been released from LDLs from the lumen of the late endosomes/lysosomes and transfers it to the cholesterol-binding pocket of the N-terminal domain of NPC1. Cholesterol binds to NPC1 with the hydroxyl group buried in the binding pocket and can be exported from the limiting membrane of late endosomes/ lysosomes into the ER and plasma membrane by an unknown mechanism.