title: Effect of Gallium Exposure in Arabidopsis thaliana is Similar to Aluminum Stress.
abstract: Although gallium (Ga) is a rare element, it is widely used in semiconductor devices. Ga contamination of the environment has been found in semiconductor-producing countries. Here, the physiological and molecular impacts of Ga in the model plant Arabidopsis thaliana were investigated in medium culture. The primary symptom of Ga toxicity is inhibition of root growth. The increased production of malondialdehyde (MDA) suggests that Ga stress could cause oxidative damage in plants. Roots were the main Ga accumulating sites. The distinctive Ga granules were deposited within the intercellular space in roots. The granules are Ga(OH)3precipitation, which indicates immobilization or limited translocation of Ga in A. thaliana. Ga stress induces root secretion of organic acids such as citrate and malate. The expression of the transporters AtALMT and AtMATE, responsible for citrate and malate secretion, respectively, were elevated under Ga stress, so the secretion may play a role in the resistance. Indeed, supplying exogenous citrate significantly enhanced Ga tolerance. The overall response to Ga exposure in A. thaliana is highly similar to that with aluminum stress. Our findings provide information for risk assessment in Ga-contaminated soil.
authors.affiliation: Department of Agricultural Chemistry, National Taiwan University , Taipei 106, Taiwan.|Agricultural Biotechnology Research Center, Academia Sinica , Taipei 115, Taiwan.
authors.forename: Hsin-Fang
authors.initials: HF
authors.lastname: Chang
authors.affiliation: Department of Agricultural Chemistry, National Taiwan University , Taipei 106, Taiwan.
authors.forename: Shan-Li
authors.initials: SL
authors.lastname: Wang
authors.affiliation: Agricultural Biotechnology Research Center, Academia Sinica , Taipei 115, Taiwan.
authors.forename: Kuo-Chen
authors.identifier: 0000-0002-3791-3423
authors.initials: KC
authors.lastname: Yeh
mesh_terms: D000535:Aluminum / Q000633:toxicity*; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D005708:Gallium; D018517:Plant Roots / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D005708:Gallium; D000535:Aluminum