title: ATP13A2/PARK9 Deficiency Neither Cause Lysosomal Impairment Nor Alter α-Synuclein Metabolism in SH-SY5Y Cells.
abstract: Parkinson's disease is a multifactorial disorder with several genes linked to the familial types of the disease. ATP13A2 is one of those genes and encode for a transmembrane protein localized in lysosomes and late endosomes. Previous studies suggested the roles of this protein in lysosomal functions and cellular ion homeostasis. Here, we set out to investigate the role of ATP13A2 in lysosomal function and in metabolism of α-synuclein, another PD-linked protein whose accumulation is implicated in the pathogenesis. We generated non-sense mutations in both copies of ATP13A2 gene in SH-SY5Y human neuroblastoma cells. We examined lysosomal function of ATP13A2-/- cells by measuring the accumulation of lysosomal substrate proteins, such as p62 and polyubiquitinated proteins, induction of acidic compartments, and degradation of ectopically introduced dextran. None of these measures were altered by ATP13A2 deficiency. The steady-state levels of α-synuclein in cells or secretion of this protein were unaltered either in ATP13A2-/- compared to the normal cells. Therefore, the proposed roles of ATP13A2 in lysosomal functions may not be generalized and may depend on the cellular context. The ATP13A2-/- cells generated in the current study may provide a useful control for studies on the roles of PD genes in lysosomal functions.
authors.affiliation: Department of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 143-701, Korea. ; Institute of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 143-701, Korea.
authors.forename: Eun-Jin
authors.initials: EJ
authors.lastname: Bae
authors.affiliation: Institute of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 143-701, Korea. ; Department of Anatomy, School of Medicine, Konkuk University, Seoul 143-701, Korea.
authors.forename: Cheolsoon
authors.initials: C
authors.lastname: Lee
authors.affiliation: Institute of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 143-701, Korea. ; Department of Anatomy, School of Medicine, Konkuk University, Seoul 143-701, Korea.
authors.forename: He-Jin
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: ToolGen, Inc., Biotechnology Incubating Center, Seoul National University, Seoul 305-390, Korea.
authors.forename: Seokjoong
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 143-701, Korea. ; Institute of Biomedical Science and Technology, School of Medicine, Konkuk University, Seoul 143-701, Korea. ; College of Veterinary Medicine, Konkuk University, Seoul 143-701, Korea.
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Lee
keywords: ATP13A2; Lysosome; PARK9; Parkinson's disease; SH-SY5Y cell; alpha-synuclein