title: Exogenous application of methyl jasmonate lowers the effect of cadmium-induced oxidative injury in rice seedlings.
abstract: Rice seedlings grown under 50 μM cadmium alone or in combination with 5 μM methyl jasmonate were investigated for Cd-induced oxidative injury at 3, 7 and 10 days of treatment. MeJA treatments alone did not have any significant change in antioxidant enzyme activities or levels of H2O2 and O2(·-) in roots/shoots, as compared to controls during 3-10 days. The Cd-stressed plants When supplemented with exogenous MeJA revealed significant and consistent changes in activities of antioxidant enzymes CAT, SOD, POD and GR paralleled with an increased GSH-pools than that in plants subjected to Cd-stress alone. Synthesis of GSH driven by increasing demand for GSH in response to Cd-induced oxidative stress in rice was evident. Increased activity of LOX under Cd-stress was noted. Results suggest enhanced Cd-tolerance, lowered Cd(2+) uptake, an improved membrane integrity and 'switching on' of the JA-biosynthesis by LOX in the Cd-stressed rice roots/shoots exposed to MeJA. Exposure to MeJA improved antioxidant response and accumulation of antioxidants which perhaps lowered the Cd-induced oxidative stress in rice. It is this switching on/off of the JA-biosynthesis and ROS mediated signal transduction pathway involving glutathione homeostasis via GR which helps MeJA to mitigate Cd-induced oxidative injury in rice.
authors.affiliation: Department of Bioinformatics, MMV, Banaras Hindu University, Varanasi 221 005, India.
authors.forename: Indra
authors.initials: I
authors.lastname: Singh
authors.affiliation: Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221 005, India. Electronic address: kavitashah69@gmail.com.
authors.forename: Kavita
authors.initials: K
authors.lastname: Shah
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D002104:Cadmium / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D003517:Cyclopentanes / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D012275:Oryza / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D054883:Oxylipins / Q000494:pharmacology*; D018517:Plant Roots / Q000378:metabolism; D036226:Seedlings / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000085:Acetates; D000975:Antioxidants; D003517:Cyclopentanes; D054883:Oxylipins; D002104:Cadmium; C072239:methyl jasmonate; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione
keywords: Antioxidant; Cadmium; Free radical; Methyl jasmonate; Rice