CLN3 is a protein that is involved in lysosomal function. CLN3 plays a vital role in lysosomal function, potentially acting as a chaperone that assists in the proper folding and unfolding of other proteins, including subunit C of the ATP synthase complex. Mutations in CLN3 gene are linked to Batten disease, a recessively inherited neurodegenerative disorder characterized by lysosomal accumulation of hydrophobic materials, primarily affecting the ATP synthase subunit C. Batten disease represents the most prevalent form of a group of disorders known as neuronal ceroid lipofuscinoses (NCLs), with symptoms that include progressive vision loss, seizures, and psychomotor disturbances, underscoring the importance of CLN3 protein in maintaining cellular health and function.