Lysosomal serine protease with tripeptidyl-peptidase I activity (PubMed:11054422, PubMed:19038966, PubMed:19038967). May act as a non-specific lysosomal peptidase which generates tripeptides from the breakdown products produced by lysosomal proteinases (PubMed:11054422, PubMed:19038966, PubMed:19038967). Requires substrates with an unsubstituted N-terminus (PubMed:19038966).
Under aberrant lysosomal storage conditions, TFEB translocated from the cytoplasm to the nucleus, resulting in the activation of its target genes.|Expression analysis of lysosomal genes after TFEB overexpression and silencing. Blue bars show the fold change of the mRNA levels of lysosomal genes in TFEB- versus pcDNA3-transfected cells.
The mammalian shelterin component TPP1 has essential roles in telomere maintenance and, together with POT1, is required for the repression of DNA damage signaling at telomeres.