Lysosme associated membrane proteins, or Lamp1 and Lamp2, are major constituents of the lysosomal membrane. The two have closely related structures, with 37% sequence homology. They are both transmembrane glycoproteins that are localized primarily in lysosomes and late endosomes. Functions descirbed for Lamp proteins include as activation markers for normal mast cells and involvement in the inflammatory response through promotion of PBMC adhesion to vascular endothelium.
Lamp1 and Lamp2 are thought to play a key role in the fusion of the autophagosome and lysosome to give the autolysosome a key late stage process during autophagy. In addition Lamp2 has also been shown to be involved in the direct targeting of proteins to the lysosome by chaperone mediated autophagy.
