title: Protein phosphatase 2A holoenzyme is targeted to peroxisomes by piggybacking and positively affects peroxisomal β-oxidation.
abstract: The eukaryotic, highly conserved serine (Ser)/threonine-specific protein phosphatase 2A (PP2A) functions as a heterotrimeric complex composed of a catalytic (C), scaffolding (A), and regulatory (B) subunit. In Arabidopsis (Arabidopsis thaliana), five, three, and 17 genes encode different C, A, and B subunits, respectively. We previously found that a B subunit, B'θ, localized to peroxisomes due to its C-terminal targeting signal Ser-Ser-leucine. This work shows that PP2A C2, C5, andA2 subunits interact and colocalize with B'θ in peroxisomes. C and A subunits lack peroxisomal targeting signals, and their peroxisomal import depends on B'θ and appears to occur by piggybacking transport. B'θ knockout mutants were impaired in peroxisomal β-oxidation as shown by developmental arrest of seedlings germinated without sucrose, accumulation of eicosenoic acid, and resistance to protoauxins indole-butyric acid and 2,4-dichlorophenoxybutyric acid. All of these observations strongly substantiate that a full PP2A complex is present in peroxisomes and positively affects β-oxidation of fatty acids and protoauxins.
authors.affiliation: Centre for Organelle Research (A.R.A.K., B.H., C.L.) and Department of Mathematics and Natural Sciences, Faculty of Science and Technology (R.K.), University of Stavanger, N-4036 Stavanger, Norway; andDepartment of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway (L.H., G.S.).
authors.forename: Amr R A
authors.initials: AR
authors.lastname: Kataya
authors.affiliation: Centre for Organelle Research (A.R.A.K., B.H., C.L.) and Department of Mathematics and Natural Sciences, Faculty of Science and Technology (R.K.), University of Stavanger, N-4036 Stavanger, Norway; andDepartment of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway (L.H., G.S.).
authors.forename: Behzad
authors.initials: B
authors.lastname: Heidari
authors.affiliation: Centre for Organelle Research (A.R.A.K., B.H., C.L.) and Department of Mathematics and Natural Sciences, Faculty of Science and Technology (R.K.), University of Stavanger, N-4036 Stavanger, Norway; andDepartment of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway (L.H., G.S.).
authors.forename: Lars
authors.initials: L
authors.lastname: Hagen
authors.affiliation: Centre for Organelle Research (A.R.A.K., B.H., C.L.) and Department of Mathematics and Natural Sciences, Faculty of Science and Technology (R.K.), University of Stavanger, N-4036 Stavanger, Norway; andDepartment of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway (L.H., G.S.).
authors.forename: Roald
authors.initials: R
authors.lastname: Kommedal
authors.affiliation: Centre for Organelle Research (A.R.A.K., B.H., C.L.) and Department of Mathematics and Natural Sciences, Faculty of Science and Technology (R.K.), University of Stavanger, N-4036 Stavanger, Norway; andDepartment of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway (L.H., G.S.).
authors.forename: Geir
authors.initials: G
authors.lastname: Slupphaug
authors.affiliation: Centre for Organelle Research (A.R.A.K., B.H., C.L.) and Department of Mathematics and Natural Sciences, Faculty of Science and Technology (R.K.), University of Stavanger, N-4036 Stavanger, Norway; andDepartment of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7489 Trondheim, Norway (L.H., G.S.) cathrine.lillo@uis.no.
authors.forename: Cathrine
authors.initials: C
authors.lastname: Lillo
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology*; D020134:Catalytic Domain; D017124:Conserved Sequence; D019143:Evolution, Molecular; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D020035:Holoenzymes / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000494:pharmacology; D050356:Lipid Metabolism / Q000187:drug effects; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D010084:Oxidation-Reduction / Q000187:drug effects; D020675:Peroxisomes / Q000187:drug effects / Q000201:enzymology*; D010641:Phenotype; D010766:Phosphorylation / Q000187:drug effects; D030821:Plants, Genetically Modified; D011485:Protein Binding / Q000187:drug effects; D054648:Protein Phosphatase 2 / Q000378:metabolism*; D021122:Protein Subunits / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects; D013395:Sucrose / Q000494:pharmacology; D014280:Triglycerides / Q000378:metabolism
chemical_list: D020035:Holoenzymes; D007210:Indoleacetic Acids; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D014280:Triglycerides; D013395:Sucrose; D054648:Protein Phosphatase 2