title: Intracellular targeting of peroxiredoxin 6 to lysosomal organelles requires MAPK activity and binding to 14-3-3ε.
abstract: Peroxiredoxin 6 (Prdx6), a bifunctional protein with GSH peroxidase and lysosomal-type phospholipase A(2) activities, has been localized to both cytosolic and acidic compartments (lamellar bodies and lysosomes) in lung alveolar epithelium. We postulate that Prdx6 subcellular localization affects the balance between the two activities. Immunostaining localized Prdx6 to lysosome-related organelles in the MLE12 and A549 alveolar epithelial cell lines. Inhibition of trafficking by brefeldin A indicated processing of the protein through the vesicular pathway. Trafficking of Prdx6 was decreased by inhibitors of PKC, ERK, and p38 MAPK. Immunocytochemistry, immunoprecipitation, and an in situ proximity ligation assay (Duolink) showed that binding of the lysosomal targeting sequence of Prdx6 (amino acids 31-40) to 14-3-3ε was dependent on activity of PKC, ERK, and p38 MAPK. Knockdown of 14-3-3ε with siRNA inhibited the lysosomal targeting of Prdx6. In vitro study with recombinant proteins by pull-down assay and surface plasmon resonance confirmed the interaction of Prdx6 and 14-3-3ε. These findings suggest that ERK and p38 MAPK regulate subcellular localization of Prdx6 by activation of 14-3-3ε as a chaperone protein, resulting in its translocation to acidic organelles.
authors.affiliation: Institute for Environmental Medicine, University of Pennsylvania, 3620 Hamilton Walk, Philadelphia, PA 19104, USA.
authors.forename: Elena M
authors.initials: EM
authors.lastname: Sorokina
authors.forename: Sheldon I
authors.initials: SI
authors.lastname: Feinstein
authors.forename: Suiping
authors.initials: S
authors.lastname: Zhou
authors.forename: Aron B
authors.initials: AB
authors.lastname: Fisher
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism*; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000378:metabolism; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D008247:Lysosomes / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D054465:Peroxiredoxin VI / Q000378:metabolism*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D048948:14-3-3 Proteins; D004791:Enzyme Inhibitors; D054465:Peroxiredoxin VI; D011493:Protein Kinase C; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases