CD107b (lysosome-associated membrane protein-2, LAMP-2), together with CD107a / LAMP-1, is a major constituent of lysosomal membrane. The LAMP proteins are involved in lysosome biogenesis and are required for fusion of lysosomes with phagosomes, especially CD107b is important regulator in successful phagosomal maturation. CD107b deficiency causes an accumulation of autophagosomes in many tissues leading to cardiomyopathy and myopathy (Danons disease). Immature CD107b is an approximately 45 kDa protein, but after extensive glycosylation the mature glycoprotein has about 100-120 kDa.
