The mitochondrial type II peroxiredoxin F is essential for redox homeostasis and root growth of Arabidopsis thaliana under stress.
Peroxiredoxins (Prx) have recently moved into the focus of plant and animal research in the context of development, adaptation, and disease, as they function both in antioxidant defense by reducing a broad range of toxic peroxides and in redox signaling relating to the adjustment of cell redox and antioxidant metabolism. At-PrxII F is one of six type II Prx identified in the genome of Arabidopsis thaliana and the only Prx that is targeted to the plant mitochondrion. Therefore, it might be assumed to have functions similar to the human 2-Cys Prx (PRDX3) and type II Prx (PRDX5) and yeast 1-Cys Prx that likewise have mitochondrial localizations. This paper presents a characterization of PrxII F at the level of subcellular distribution, activity, and reductive regeneration by mitochondrial thioredoxin and glutaredoxin. By employing tDNA insertion mutants of A. thaliana lacking expression of AtprxII F (KO-AtPrxII F), it is shown that under optimal environmental conditions the absence of PrxII F is almost fully compensated for, possibly by increases in activity of mitochondrial ascorbate peroxidase and glutathione-dependent peroxidase. However, a stronger inhibition of root growth in KO-AtPrxII F seedlings as compared with wild type is observed under stress conditions induced by CdCl2 as well as after administration of salicylhydroxamic acid, an inhibitor of cyanide-insensitive respiration. Simultaneously, major changes in the abundance of both nuclear and mitochondria-encoded transcripts were observed. These results assign a principal role to PrxII F in antioxidant defense and possibly redox signaling in plants cells.
Finkemeier
Iris
I
Department of Plant Physiology and Biochemistry, University of Bielefeld, 33501 Bielefeld, Germany.
Goodman
Megan
M
Lamkemeyer
Petra
P
Kandlbinder
Andrea
A
Sweetlove
Lee J
LJ
Dietz
Karl-Josef
KJ
D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D000595:Amino Acid Sequence; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology; D017360:Arabidopsis / Q000378:metabolism*; D001205:Ascorbic Acid / Q000737:chemistry; D015153:Blotting, Western; D002104:Cadmium / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation; D003600:Cytosol / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D005978:Glutathione / Q000378:metabolism; D006706:Homeostasis; D007150:Immunohistochemistry; D008928:Mitochondria / Q000378:metabolism; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism; D010101:Oxygen Consumption; D010544:Peroxidases / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D010545:Peroxides / Q000378:metabolism; D054464:Peroxiredoxins; D010636:Phenols; D010641:Phenotype; D018517:Plant Roots / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000378:metabolism; D013454:Sulfoxides; D013997:Time Factors; D014018:Tissue Distribution; D014992:Xylenes / Q000494:pharmacology
D000975:Antioxidants; D010545:Peroxides; D010636:Phenols; D011994:Recombinant Proteins; D013454:Sulfoxides; D014992:Xylenes; D002104:Cadmium; D000255:Adenosine Triphosphate; D004247:DNA; D010544:Peroxidases; C515974:PRDX5 protein, human; D054464:Peroxiredoxins; D005978:Glutathione; D001205:Ascorbic Acid; C016833:xylenol orange; D010100:Oxygen