title: The role of ferredoxin:thioredoxin reductase/thioredoxin m in seed germination and the connection between this system and copper ion toxicity.
abstract: Seed germination is highly sensitive to changes in the surrounding environment. This work examined the impact of imbibition with copper solution on the germination rate and behavior of some enzyme capacities involved in stress response. Chickpea (Cicer arietinum L.) seeds were germinated at 25°C in the dark for 7 days of imbibition with distilled water or an aqueous solution of chloride salt of 100 or 500μM CuCl2. The exposure of seeds to copper (Cu(2+)) induced changes in the antioxidant status. In Cu-treated seeds, the non-protein thiols (—SHNP) pool and ferredoxin:thioredoxin reductase (FTR) expression and activity increased. Cysteinyl sulfurs in the thioredoxin (Trx) function as ligands for metal ions. The accumulation of Cu(2+) inhibited seed germination and embryo growth. It appears that the FTR system mediates a novel form of redox signaling in plants under copper excess.
authors.affiliation: Department of Biotechnology, University of Carthage, Higher Institute of Sciences and Technology of Environment, Technopole of Borj Cedria, B.P. n° 1003, Hammam Lif 2050, Tunisia. Electronic address: smirimoez@yahoo.fr.
authors.forename: M
authors.initials: M
authors.lastname: Smiri
authors.affiliation: Department of Biotechnology, University of Carthage, Higher Institute of Sciences and Technology of Environment, Technopole of Borj Cedria, B.P. n° 1003, Hammam Lif 2050, Tunisia. Electronic address: Takwamissaoui728@yahoo.com.
authors.forename: T
authors.initials: T
authors.lastname: Missaoui
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D018533:Biomass; D054479:Chloroplast Thioredoxins / Q000378:metabolism*; D029863:Cicer / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D003300:Copper / Q000633:toxicity*; D005288:Ferredoxins / Q000378:metabolism; D018525:Germination; D007506:Iron-Sulfur Proteins / Q000235:genetics / Q000378:metabolism*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D015398:Signal Transduction
chemical_list: D000975:Antioxidants; D054479:Chloroplast Thioredoxins; D005288:Ferredoxins; D007506:Iron-Sulfur Proteins; D010940:Plant Proteins; D003300:Copper; D010088:Oxidoreductases; C021588:ferredoxin-thioredoxin reductase; C029892:cupric chloride
keywords: Antioxidant; Cicer arietinum; Ferredoxin; Non-protein thiols; Thioredoxin reductase