Lysosomal serine protease with tripeptidyl-peptidase I activity. May act as a non-specific lysosomal peptidase which generates tripeptides from the breakdown products produced by lysosomal proteinases. Requires substrates with an unsubstituted N-terminus. Defects in TPP1 are the cause of neuronal ceroid lipofuscinosis type 2 (CLN2). A form of neuronal ceroid lipofuscinosis. Neuronal ceroid lipofuscinoses are progressive neurodegenerative, lysosomal storage diseases characterized by intracellular accumulation of autofluorescent liposomal material, and clinically by seizures, dementia, visual loss, and/or cerebral atrophy. The lipopigment pattern seen most often in CLN2 consists of curvilinear profiles. Belongs to the peptidase S53 family. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: EC 126.96.36.199; Mitochondrial; Protease; Secreted; Secreted, signal peptide
Biological Process: bone resorption; central nervous system development; epithelial cell differentiation; lipid metabolic process; lysosome organization and biogenesis; nervous system development; neuromuscular process controlling balance; peptide catabolic process; proteolysis