title: Proteomic analysis provides insights into the molecular bases of hydrogen gas-induced cadmium resistance in Medicago sativa.
abstract: Recently, molecular hydrogen (H2) has emerged as a bio-regulator both in animals and plants. Normally, functions of endogenous generated H2could be mimicked by exogenously applied hydrogen-rich water (HRW) or hydrogen-rich saline (particularly in animals). Although alfalfa seedlings showed more cadmium (Cd) resistance after the administration with HRW, corresponding molecular mechanism is still elusive. To address this gap, iTRAQ-based quantitative proteomics was used. The results showed that a total of 2377 proteins were identified with <1% FDR, and 1254 protein abundance perturbations were confidently assessed. Total of 248 significant differential proteins were identified in Cd- and/or HRW-treated samples. Furthermore, 92 proteins from the 248 proteins were selected for further bioinformatics analysis. Interestingly, results indicated that they were classified into seven categories: defense and response to stress, sulfur compound metabolic process, amino acid and protein metabolic process, carbohydrate and energy metabolic process, secondary metabolic process, oxidation-reduction process, and metal ion homeostasis. In addition, the protein expression patterns were consistent with the results of decreased lipid peroxidation, increased non-protein thiols abundance, as well as iron and zinc content. These suggest that HRW alleviates Cd toxicity mainly by decreasing oxidative damage, enhancing sulfur compound metabolic process, and maintaining nutrient element homeostasis.
  
  
  
  Contamination of soils by Cd has become a potential concern to crops. Medicago sativa is a widely used forage around the world. Recently, hydrogen gas (H2) was suggested as a candidate of signal molecule, and found to effectively attenuate Cd-induced damage in alfalfa seedlings. However, the underlying molecular mechanism still needs to be further elucidated. In the present work, an iTRAQ-based quantitative proteomics was firstly carried out, and the results revealed the main molecular targets and metabolic processes associated with Cd resistance conferred by H2. This study may expand our understanding of hydrogen gas-medicated heavy metal tolerance in plants.
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China; Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Dai
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Weiti
authors.initials: W
authors.lastname: Cui
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Jincheng
authors.initials: J
authors.lastname: Pan
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: wbshenh@njau.edu.cn.
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Shen
mesh_terms: D002104:Cadmium / Q000494:pharmacology* / Q000633:toxicity; D019295:Computational Biology; D004351:Drug Resistance / Q000187:drug effects*; D006859:Hydrogen / Q000494:pharmacology*; D000455:Medicago sativa / Q000502:physiology*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010940:Plant Proteins / Q000032:analysis / Q000187:drug effects; D020543:Proteome / Q000032:analysis / Q000187:drug effects*; D040901:Proteomics / Q000379:methods*; D036226:Seedlings / Q000378:metabolism; D012989:Soil Pollutants / Q000494:pharmacology / Q000633:toxicity; D013457:Sulfur Compounds / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D020543:Proteome; D012989:Soil Pollutants; D013457:Sulfur Compounds; D002104:Cadmium; D006859:Hydrogen
keywords: Cadmium; Medicago sativa; Molecular hydrogen; iTRAQ