Mediates microtubule-dependent, anterograde transport connecting the Golgi network, endosomes, autophagosomes, lysosomes and plasma membrane, and participates in several cellular processes such as regulation of lysosomal pH, lysosome protein degradation, receptor-mediated endocytosis, autophagy, transport of proteins and lipids from the TGN, apoptosis and synaptic transmission (PubMed:10924275, PubMed:18817525, PubMed:18317235, PubMed:22261744, PubMed:15471887, PubMed:20850431). Facilitates the proteins transport from trans-Golgi network (TGN)-to other membrane compartments such as transport of microdomain-associated proteins to the plasma membrane, IGF2R transport to the lysosome where it regulates the CTSD release leading to regulation of CTSD maturation and thereby APP intracellular processing (PubMed:10924275, PubMed:18817525). Moreover regulates CTSD activity in response to osmotic stress (PubMed:23840424, PubMed:28390177). Also binds galactosylceramide and transports it from the trans Golgi to the rafts, which may have immediate and downstream effects on cell survival by modulating ceramide synthesis (PubMed:18317235). At the plasma membrane, regulates actin-dependent events including filopodia formation, cell migration, and pinocytosis through ARF1-CDC42 pathway and also the cytoskeleton organization through interaction with MYH10 and fodrin leading to the regulation of the plasma membrane association of Na+, K+ ATPase complex (PubMed:20850431). Regulates synaptic transmission in the amygdala, hippocampus, and cerebellum through regulation of synaptic vesicles density and their proximity to active zones leading to modulation of short-term plasticity and age-dependent anxious behavior, learning and memory (By similarity). Regulates autophagic vacuoles (AVs) maturation by modulating the trafficking between endocytic and autophagolysosomal/lysosomal compartments, which involves vesicle fusion leading to regulation of degradation process (By similarity). Participates also in cellular homeostasis of compounds such as, water, ions, amino acids, proteins and lipids in several tissue namely in brain and kidney through regulation of their transport and synthesis (PubMed:17482562). Homooligomer (By similarity). Interacts with DCTN1, KIF3A, RAB7A and RILP (PubMed:22261744). Interacts with CLN5 (PubMed:19941651, PubMed:14699076). May interact with HOOK1 (PubMed:15471887). Interacts with KCNIP3; this interaction is disrupted by intracellular increase of calcium level (PubMed:17189291). Interacts with TPP1, CLN6 AND CLN8 (PubMed:17237713). Interacts with MYH10; this interaction may play a role in regulation of cytoskeleton organization (PubMed:20850431). Interacts with SBDS (PubMed:20015955). Interacts with sodium/potassium-transporting ATPase complex (via ATP1A1) and fodrin heteromer (via SPTAN1); this interaction regulates their localization at the plasma membrane (Probable). Interacts with HSPA5 (Probable). Interacts (via dileucine motif) with AP3D1 and AP1G1; this interaction facilitates lysosomal targeting (PubMed:15598649). Interacts (via dileucine motif) with AP2A2 (PubMed:15598649). CLN3 is not present in late endosomes/lysosomes in fibroblasts and neurons (PubMed:15240864). Trafficks from cell membrane to Golgi via endosomes (PubMed:15240864). Osmotic stress changes the subcellular localization of CLN3 (PubMed:23840424). Trafficks to intracellular compartments via the plasma membranet through AP3M1-dependent mechanisms (PubMed:14644441). Excluded from the synaptic vesicles (By similarity). Additional isoforms seem to exist. Expressed in the cortical brain, pancreas, spleen, and testis with weaker expression in the peripheral nerve (at protein level). Highly expressed in gray matter (at protein level). Increased by osmotic stress. The C-terminal (153-438) mediates KCNIP3 interaction and the cytoprotective activity (PubMed:17189291). the dileucine motif mediates AP1G1 and AP3D1 interaction (PubMed:15598649). Highly glycosylated. Farnesylation is important for trafficking to lysosomes. Phosphorylated on both serine and threonine residues by PKA, PKG and CK2. The disease is caused by variants affecting the gene represented in this entry. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the battenin family. Mao et al suggest that CLN3 has five transmembranes with a long lumenal N-terminus because their antibody does not immunoprecipitate the N-terminus in the presence of microsomes. Neural Ceroid Lipofuscinoses mutation db Retina International's Scientific Newsletter