Interactive effects of nitric oxide and glutathione in mitigating copper toxicity of rice (Oryza sativa L.) seedlings

• Published in: Plant signaling & behavior 2015-01, Vol.10 (3), p.e991570
• Main Authors: Mostofa, Mohammad Golam, Seraj, Zeba Islam, Fujita, Masayuki
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological; Antioxidants - metabolism; Copper - metabolism; Copper - toxicity; copper tolerance; glutathione; Glutathione - metabolism; Glutathione - pharmacology; GSNO signaling; nitric oxide; Nitric Oxide - metabolism; Nitric Oxide Donors - metabolism; Nitric Oxide Donors - pharmacology; Nitroprusside - metabolism; Nitroprusside - pharmacology; Oryza - drug effects; Oryza - metabolism; Oryza sativa L; Oxidative Stress; proline; Proline - metabolism; Reactive Oxygen Species - metabolism; S-Nitrosoglutathione - metabolism; S-nitrosylation; Seedlings - metabolism; Short Communication; Up-Regulation
• ISSN: 1559-2316; 1559-2324; 1559-2324
• DOI: 10.4161/15592324.2014.991570

Nitric oxide (NO) and glutathione (GSH) are 2 vital components of the antioxidant system that play diverse roles in plant responses to abiotic stresses. Recently, we have reported that exogenous supply of both these molecules reduced copper (Cu) toxicity in rice seedlings. Individual as well as co-treatment of sodium nitroprusside (SNP: a NO donor) and GSH with Cu significantly mitigated the adverse effects of Cu, evident in the reduced level of oxidative markers such as H 2 O 2 , superoxide (O 2 ·− ), malondialdehyde (MDA), and proline (Pro). GSH content and most of the antioxidative and glyoxalase enzymes were up-regulated upon Cu stress, indicating their responses were co-related with the level of stress. Our results indicated that direct ROS scavenging, reduced Cu uptake, and the balanced antioxidative and glyoxalase systems, at least in part, successfully executed NO- and GSH-mediated alleviation of Cu toxicity in rice seedlings. In addition, the combined effect of adding SNP and GSH together was more efficient than the effect of adding them individually. Here, we are speculating that 1) GSH and Pro could be used as potential markers for copper stress, and 2) adding SNP and GSH might produce S-nitrosoglutathione (GSNO) which could be a source of bioactive NO and may affect many regulatory processes involved in Cu-stress tolerance. We further note that the combined effect of adding SNP and GSH was pronounced in inhibiting the uptake and translocation of Cu in rice seedlings.