Plays an important role in chaperone-mediated autophagy, a process that mediates lysosomal degradation of proteins in response to various stresses and as part of the normal turnover of proteins with a long biological half-live (PubMed:10972293). Functions by binding target proteins, such as GAPDH and MLLT11, and targeting them for lysosomal degradation (By similarity). Required for the fusion of autophagosomes with lysosomes during autophagy (PubMed:27628032). Cells that lack LAMP2 express normal levels of VAMP8, but fail to accumulate STX17 on autophagosomes, which is the most likely explanation for the lack of fusion between autophagosomes and lysosomes (PubMed:27628032). Required for normal degradation of the contents of autophagosomes (PubMed:10972293, PubMed:12221139). Plays a role in lysosomal protein degradation in response to starvation (PubMed:27628032). Required for efficient MHCII-mediated presentation of exogenous antigens via its function in lysosomal protein degradation; antigenic peptides generated by proteases in the endosomal/lysosomal compartment are captured by nascent MHCII subunits. Is not required for efficient MHCII-mediated presentation of endogenous antigens (By similarity). Monomer. Forms large homooligomers. Interacts (via its cytoplasmic region) with HSPA8. Interacts with HSP90 in the lysosome lumen; this enhances LAMP2 stability (By similarity). Interacts with MLLT11 (By similarity). Interacts with ABCB9 (PubMed:22641697). Interacts with FURIN (By similarity). This protein shuttles between lysosomes, endosomes, and the plasma membrane. Detected in liver and kidney (at protein level). Detected in liver and kidney. Extensively N-glycosylated. Contains a minor proportion of O-linked glycans. About half of the mutant mice die between 20 and 40 days after birth. Survivors are smaller, weigh 10 to 15 % less than their littermates, but show normal lifespan. Both mice that die early and long-time survivors display an accumulation of autophagic vacuoles in liver, pancreas, cardiac and skeletal muscle. Mutant mice display an increased ratio of heart weight to body weight and severely impaired contractile function of the heart muscle. Hepatocytes from mutant mice show a decreased rate of degradation of long-lived proteins. Belongs to the LAMP family.