title: A putative lambda class glutathione S-transferase enhances plant survival under salinity stress.
abstract: In a survey of candidate genes located in the salinity tolerance locus of soybean, we identified a putative glutathione S-transferase (GST) gene (GmGSTL1) which was up-regulated in response to salt treatment. Phylogenetic analyses revealed that this putative GST belongs to the Lambda class, a plant-specific group with unknown functions. We expressed GmGSTL1 in heterologous systems, including tobacco BY-2 cells and Arabidopsis thaliana, to test its ability to protect the cell/plant against salinity stress. Compared with the control, we observed a marked reduction of reactive oxygen species (ROS) accumulation in transgenic cells under salt treatment, and their survival rate was also improved. Similarly, expression of GmGST1 in transgenic A. thaliana also alleviated stress symptoms under salt treatment. To address further the possible protective mechanisms of GmGSTL1, we identified two candidate flavonoid interactants (quercetin and kaemferol) of the GmGSTL1 protein from soybean leaf extract. Exogenous application of quercetin could reduce salinity-induced ROS accumulation in BY-2 cells and leaf chlorosis in A. thaliana.
authors.affiliation: Center for Soybean Research of the State Key Laboratory of Agrobiotechnology and School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
authors.forename: Ching
authors.initials: C
authors.lastname: Chan
authors.forename: Hon-Ming
authors.initials: HM
authors.lastname: Lam
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D011794:Quercetin / Q000378:metabolism; D054712:Salinity; D012965:Sodium Chloride / Q000494:pharmacology; D013025:Glycine max / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D014026:Nicotiana / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics
chemical_list: D010940:Plant Proteins; D012965:Sodium Chloride; D011794:Quercetin; D005982:Glutathione Transferase
keywords: Glutathione S-transferase; Oxidative stress; Salinity; Soybean