NPC1 (E7S4N) Rabbit mAb #33422

Niemann-Pick type C (NPC) disease is a lysosomal storage disease in which endocytosed cholesterol becomes sequestered in late endosomes/lysosomes (LEs/Ls) due to mutations in either the NPC1 or NPC2 gene, which encode NPC1 (Niemann-Pick type C1) or NPC2 (Niemann-Pick type C2) protein (1,2). NPC1 is a multipass transmembrane protein located at the LEs/Ls membrane, and NPC2 is located in the lumen of the vesicles. NPC2 directly binds to sequestered unesterified cholesterol in the lumen and delivers the cholesterol to the N-terminal domain of membrane-bound NPC1. The cholesterol further interacts with the sterol-sensing domain of NPC1 and is eventually exported from LEs/Ls to Golgi, ER, or plasma membrane (3,4). In cells with dysfunctional NPC1, cholesterol is sequestered in the lysosome, resulting in lysosomal dysfunction and NPC. Loss of function of NPC1 leads to progressive neurodegeneration (5), neuroinflammation and myelin defects, severe neonatal liver disease and lung failure, and immune dysfunction (1,6,7). Elevated NPC1 is linked to cancer progression and drug resistance. Reagents that target NPC1 activity provide opportunities for disease treatment strategies (8,9).