Examinando por Autor "Airaki, Morad"
Mostrando 1 - 2 de 2
- Resultados por página
- Opciones de ordenación
Ítem Metabolism of reactive nitrogen species in pea plants under abiotic stress conditions(OXFORD UNIV PRESS, 2008-09-18) Corpas, Francisco Javier; Chaki, Mounira; Fernández-Ocaña, Ana; Valderrama, Raquel; Palma, José Manuel; Carreras, Alfonso; Begara-Morales, Juan Carlos; Airaki, Morad; del-Río, Luis Alfonso; Barroso-Albarracín, Juan BautistaNitric oxide (NO) is a key signaling molecule in different physiological processes of animals and plants. However, little is known about the metabolism of endogenous NO and other reactive nitrogen species (RNS) in plants under abiotic stress conditions. Using pea plants exposed to six different abiotic stress conditions (high light intensity, low and high temperature, continuous light, continuous dark and mechanical wounding), several key components of the metabolism of RNS including the content of NO, S-nitrosothiols (RSNOs) and nitrite plus nitrate, the enzyme activities of L-arginine dependent nitric oxide synthase (NOS) and S-nitrosogluthathione reductase (GSNOR), and the profile of protein tyrosine nitration (NO2-Tyr) were analyzed in leaves. Low temperature was the stress that produced the highest increase of NOS and GSNOR activities, and this was accompanied by an increase in the content of total _NO and S-nitrosothiols, and an intensification of the immunoreactivity with an antibody against NO2-Tyr. Mechanical wounding, high temperature and light also had a clear activating effect on the different indicators of RNS metabolism in pea plants. However, the total content of nitrite and nitrate in leaves was not affected by any of these stresses. Considering that protein tyrosine nitration is a potential marker of nitrosative stress, the results obtained suggest that low and high temperature, continuous light and high light intensity are abiotic stress conditions that can induce nitrosative stress in pea plants.Ítem Metabolism of reactive oxygen species and reactive nitrogen species in pepper (Capsicum annuum L.) plants under low temperature stress(WILEY, 2012-02) Airaki, Morad; Leterrier, Marina; Mateos, Rosa María; Valderrama, Raquel; Chaki, Mounira; Barroso-Albarracín, Juan Bautista; del-Río, Luis Alfonso; Palma, José Manuel; Corpas, Francisco JavierLow temperature is an environmental stress that affects crop production and quality and regulates the expression of many genes, and the level of a number of proteins and metabolites. Using leaves from pepper (Capsicum annum L.) plants exposed to low temperature (8°C) for different time periods (1 to 3d), several key components of the metabolism of reactive nitrogen and oxygen species (RNS and ROS, respectively) were analysed. After 24h of exposure at 8°C, pepper plants exhibited visible symptoms characterized by flaccidity of stems and leaves. This was accompanied by significant changes in the metabolism of RNS and ROS with an increase of both protein tyrosine nitration (NO2-Tyr) and lipid peroxidation, indicating that low temperature induces nitrosative and oxidative stress. During the second and third days at low temperature, pepper plants underwent cold acclimation by adjusting their antioxidant metabolism and reverting the observed nitrosative and oxidative stress. In this process, the levels of the soluble non-enzymatic antioxidants ascorbate and glutathione, and the activity of the main NADPH-generating dehydrogenases were significantly induced. This suggests that ascorbate, glutathione and the NADPH-generating dehydrogenases have a role in the process of cold acclimation through their effect on the redox state of the cell.