Proteomic responses to lead-induced oxidative stress in Talinum triangulare Jacq. (Willd.) roots: identification of key biomarkers related to glutathione metabolisms.
In this study, Talinum triangulare Jacq. (Willd.) treated with different lead (Pb) concentrations for 7 days has been investigated to understand the mechanisms of ascorbate-glutathione metabolisms in response to Pb-induced oxidative stress. Proteomic study was performed for control and 1.25 mM Pb-treated plants to examine the root protein dynamics in the presence of Pb. Results of our analysis showed that Pb treatment caused a decrease in non-protein thiols, reduced glutathione (GSH), total ascorbate, total glutathione, GSH/oxidized glutathione (GSSG) ratio, and activities of glutathione reductase and γ-glutamylcysteine synthetase. Conversely, cysteine and GSSG contents and glutathione-S-transferase activity was increased after Pb treatment. Fourier transform infrared spectroscopy confirmed our metabolic and proteomic studies and showed that amino, phenolic, and carboxylic acids as well as alcoholic, amide, and ester-containing biomolecules had key roles in detoxification of Pb/Pb-induced toxic metabolites. Proteomic analysis revealed an increase in relative abundance of 20 major proteins and 3 new proteins (appeared only in 1.25 mM Pb). Abundant proteins during 1.25 mM Pb stress conditions have given a very clear indication about their involvement in root architecture, energy metabolism, reactive oxygen species (ROS) detoxification, cell signaling, primary and secondary metabolisms, and molecular transport systems. Relative accumulation patterns of both common and newly identified proteins are highly correlated with our other morphological, physiological, and biochemical parameters.
Department of Plant Sciences, University of Hyderabad, Hyderabad, 500046, India, kkumar.abhay@gmail.com.
Abhay
A
Kumar
Narasimha Vara Prasad
NV
Majeti
D001205:Ascorbic Acid / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D005978:Glutathione / Q000378:metabolism*; D005980:Glutathione Reductase / Q000378:metabolism; D007854:Lead / Q000633:toxicity*; D019684:Magnoliopsida / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010940:Plant Proteins / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D010944:Plants / Q000378:metabolism; D029622:Portulacaceae / Q000187:drug effects* / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D040901:Proteomics; D017382:Reactive Oxygen Species / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D013312:Stress, Physiological; D013438:Sulfhydryl Compounds / Q000378:metabolism
D015415:Biomarkers; D010940:Plant Proteins; D011506:Proteins; D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D007854:Lead; D005980:Glutathione Reductase; D005978:Glutathione; D003545:Cysteine; D001205:Ascorbic Acid