u-0126 and 1-3-dihydroxy-4-4-5-5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole

This study investigated the relationship between MEK1/2 and nitric oxide (NO) in jasmonic acid (JA)-regulated metabolism of ascorbate and glutathione in maize leaves. The results showed that JA increased the activities of APX, GR, MDHAR, DHAR, GalLDH, and γ-ECS; the contents of AsA and GSH; and the production of NO. Above increases except for γ-ECS activity and NO production were all suppressed by pre-treatments with MEK1/2 inhibitors PD98059 and U0126. Above increases were all suppressed by pre-treatments with nitric oxide synthase (NOS) inhibitor L-NAME and NO scavenger cPTIO. The results of western blot showed that JA enhanced the phosphorylation level of MEK1/2. Pre-treatments with L-NAME and cPTIO suppressed JA-induced phosphorylation level of MEK1/2. Our results suggested that JA-induced NO activated MEK1/2 by increasing the phosphorylation level, which, in turn, resulted in the upregulation of ascorbate and glutathione metabolism in maize leaves.

Topics: Ascorbic Acid; Benzoates; Butadienes; Cyclopentanes; Flavonoids; Glutathione; Imidazoles; Mitogen-Activated Protein Kinase Kinases; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitriles; Oxylipins; Phosphorylation; Plant Leaves; Zea mays