Lysosome-associated membrane proteins (LAMP) are glycosylated type I membrane proteins that play a role in the biogenesis of the pigment melanin. LAMP-1 (also designated CD107a) and LAMP-2 (also designated CD107b) are involved in a variety of functions, including cellular adhesion, and are thought to participate in the process of tumor invasion and metastasis. Both are transmembrane proteins and are heavily glycosylated at the amino-terminal luminal side of the lysosomal inner leaflet, which protects the proteins from proteolysis . The carboxy terminus of LAMP1 is exposed to the cytoplasm and contains a tyrosine sorting motif that targets LAMP to lysosomal membranes .
