Artículos de revistas
Nitric oxide synthase-like dependent NO production enhances heme oxygenase up-regulation in ultraviolet-B-irradiated soybean plants
Fecha
2010-10Registro en:
Santa Cruz, Diego Mario; Pacienza, Natalia Alejandra; Polizio, Ariel Héctor; Balestrasse, Karina Beatriz; Tomaro, Maria Lujan; et al.; Nitric oxide synthase-like dependent NO production enhances heme oxygenase up-regulation in ultraviolet-B-irradiated soybean plants; Elsevier; Phytochemistry; 71; 14-15; 10-2010; 1700-1707
0031-9422
Autor
Santa Cruz, Diego Mario
Pacienza, Natalia Alejandra
Polizio, Ariel Héctor
Balestrasse, Karina Beatriz
Tomaro, Maria Lujan
Yannarelli, Gustavo Gabriel
Resumen
Heme oxygenase (HO) has antioxidant properties and is up-regulated by reactive oxygen species (ROS) in ultraviolet-B-irradiated soybean plants. This study shows that nitric oxide (NO) protects against oxidative damage and that nitric oxide synthase (NOS)-like activity is also required for HO-1 induction under UV-B radiation. Pre-treatments with sodium nitroprussiate (SNP), a NO-donor, prevented chlorophyll loss, H2O2 and View the MathML source accumulation, and ion leakage in UV-B-treated plants. HO activity was significantly enhanced by NO and showed a positive correlation with HO-1 transcript levels. In fact, HO-1 mRNA levels were increased 2.1-fold in 0.8 mM SNP-treated plants, whereas subsequent UV-B irradiation augmented this expression up to 3.5-fold with respect to controls. This response was not observed using ferrocyanide, a SNP inactive analog, and was effectively blocked by 2-(4-carboxyphenil)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), a specific NO-scavenger. In addition, experiments carried out in the presence of NG-nitro-l-arginine methyl ester (l-NAME) or tungsten, well-known inhibitors of NOS and nitrate reductase, showed that NOS is the endogenous source of NO that mediates HO-1 expression. In summary, we found that NO is involved in the signaling pathway leading to HO-1 up-regulation under UV-B, and that a balance between NO and ROS is important to trigger the antioxidant response against oxidative stress.