title: Responses of transgenic Arabidopsis plants and recombinant yeast cells expressing a novel durum wheat manganese superoxide dismutase TdMnSOD to various abiotic stresses.
abstract: In plant cells, the manganese superoxide dismutase (Mn-SOD) plays an elusive role in the response to oxidative stress. In this study, we describe the isolation and functional characterization of a novel Mn-SOD from durum wheat (Triticum turgidum L. subsp. Durum), named TdMnSOD. Molecular phylogeny analysis showed that the durum TdMnSOD exhibited high amino acids sequence identity with other Mn-SOD plants. The three-dimensional structure showed that TdMnSOD forms a homotetramer and each subunit is composed of a predominantly α-helical N-terminal domain and a mixed α/β C-terminal domain. TdMnSOD gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdMnSOD enhances tolerance of the transformed yeast cells to salt, osmotic, cold and H2O2-induced oxidative stresses. Moreover, the analysis of TdMnSOD transgenic Arabidopsis plants subjected to different environmental stresses revealed low H2O2 and high proline levels as compared to the wild-type plants. Compared with the non-transformed plants, an increase in the total SOD and two other antioxidant enzyme activities including catalase (CAT) and peroxidases (POD) was observed in the three transgenic lines subjected to abiotic stress. Taken together, these data provide evidence for the involvement of durum wheat TdMnSOD in tolerance to multiple abiotic stresses in crop plants.
authors.affiliation: Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, Tunisia.
authors.forename: Feki
authors.initials: F
authors.lastname: Kaouthar
authors.affiliation: Laboratory of Microorganisms and Biomolecules, Centre of Biotechnology of Sfax, Tunisia.
authors.forename: Farhat-Khemakhem
authors.initials: FK
authors.lastname: Ameny
authors.affiliation: Laboratory of Molecular Biotechnology of Eukaryotes, Centre of Biotechnology of Sfax, Tunisia.
authors.forename: Kamoun
authors.initials: K
authors.lastname: Yosra
authors.affiliation: Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, Tunisia.
authors.forename: Saibi
authors.initials: S
authors.lastname: Walid
authors.affiliation: Laboratory of Molecular Biotechnology of Eukaryotes, Centre of Biotechnology of Sfax, Tunisia.
authors.forename: Gargouri
authors.initials: G
authors.lastname: Ali
authors.affiliation: Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, Tunisia. Electronic address: faical.brini@cbs.rnrt.tn.
authors.forename: Brini
authors.initials: B
authors.lastname: Faiçal
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000595:Amino Acid Sequence; D000975:Antioxidants / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D006706:Homeostasis; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000235:genetics; D030821:Plants, Genetically Modified; D011995:Recombination, Genetic / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D020539:Sequence Analysis, Protein; D013312:Stress, Physiological; D013482:Superoxide Dismutase / Q000737:chemistry / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D014908:Triticum / Q000201:enzymology* / Q000235:genetics / Q000502:physiology
chemical_list: D000975:Antioxidants; D013481:Superoxides; D013482:Superoxide Dismutase
keywords: Abiotic stress; Antioxidant enzymes; Oxidative stress; Reactive oxygen species; Superoxide dismutase; Triticum durum