The apoplastic antioxidant system in Prunus: response to long-term plum pox virus infection

Abstract

This work describes, for the first time, the changes taking place in the antioxidative system of the leaf apoplast in response to plum pox virus (PPV) in different Prunus species showing different susceptibilities to PPV. The presence of p-hydroxymercuribenzoic acid (pHMB)-sensitive ascorbate peroxidase (APX) (class I APX) and pHMB-insensitive APX (class III APX), superoxide dismutase (SOD), peroxidase (POX), NADH-POX, and polyphenoloxidase (PPO) was described in the apoplast from both peach and apricot leaves. PPV infection produced different changes in the antioxidant system of the leaf apoplast from the Prunus species, depending on their susceptibility to the virus. In leaves of the very susceptible peach cultivar GF305, PPV brought about an increase in class I APX, POX, NADH-POX, and PPO activities. In the susceptible apricot cultivar Real Fino, PPV infection produced a decrease in apoplastic POX and SOD activities, whereas a strong increase in PPO was observed. However, in the resistant apricot cultivar Stark Early Orange, a rise in class I APX as well as a strong increase in POX and SOD activities was noticed in the apoplastic compartment. Long-term PPV infection produced an oxidative stress in the apoplastic space from apricot and peach plants, as observed by the increase in H2O2 contents in this compartment. However, this increase was much higher in the PPV-susceptible plants than in the resistant apricot cultivar. Only in the PPV-susceptible apricot and peach plants was the increase in apoplastic H2O2 levels accompanied by an increase in electrolyte leakage. No changes in the electrolyte leakage were observed in the PPV-inoculated resistant apricot leaves, although a 42% increase in the apoplastic H2O2 levels was produced. Two-dimensional electrophoresis analyses revealed that the majority of the polypeptides in the apoplastic fluid had isoelectric points in the range of pI 4-6. The identification of proteins using MALDI-TOF (matrix-assisted laser desorption/ionization-time of flight) and peptide mass fingerprinting analyses showed the induction of a thaumatin-like protein as well as the decrease of mandelonitrile lyase in peach apoplast due to PPV infection. However, most of the selected polypeptides showed no homology with known proteins. This fact emphasizes that, at least in Prunus, most of the functions of the apoplastic space remain unknown. It is concluded that long-term PPV infection produced an oxidative stress in the leaf apoplast, contributing to the deleterious effects produced by PPV infection in leaves of inoculated, susceptible Prunus plants.

Biochemical Characterization of Compatible Plant Virus Interaction: A Case Study with Bunchy Top Virus-Banana Host-Pathosystem

“…4a). This result is in accordance with the results of Tobacco mosaic virus infected tobacco (Lagrimini and Rothstein,1987), plum pox virus infected peaches, apricots (Diaz-Vivancos et al, 2006), Beans yellow mosaic virus infected beans (Radwan et al, 2010), Potato virus Y infected potato (Milavec et al, 2001), tomato and bell pepper infected with Tobacco mosaic virus and Tomato mosaic tobamo virus (Madhusudhan et al, 2009), Cucumber mosaic virus and Zucchini yellow mosaic virus infected Cucumis sativus and Cucurbita pepo plants ( Riedle-Bauer, 2000), Tobacco mosaic virus infected tobacco plants (Kiraly et al, 2002), Tomato yellow leaf curl virus infected tomato plants (Dieng et al, 2011), Banana bunchy top virus infected cultivars of banana (Devanathan et al, 2005), geminivirus infected Capsicum annum (Meena et al, 2008) and cotton with CLCuBuV (Siddique et al, 2014). Virus infection appears to stimulate POX activity in all hosts in (Wood, 1990).…”

Reactive oxygen and nitrogen species and hormone signalling in systemic infection of pea by Pea enation mosaic virus

“…Minor changes in the activity of enzymes, lipid peroxidation, and hydrogen peroxide content were found in susceptible hosts (Madhusudhan et al 2009). Long-term infection by plum pox virus studied by Díaz-Vivancos et al (2006) in peach and apricot showed that general increase in H 2 O 2 concentration led to lipid hydroperoxidation of cell membranes and proteins in susceptible, but not in resistant hosts. In compatible interactions, ion leakage, a marker of damaged plasmalemma, was accompanied by a decrease in POX and superoxide dismutase activity, whereas in the incompatible interactions, the activities of these enzymes were increased.…”

“…The variation in the level of reactive nitrogen and oxygen species (RONS) is viewed as a common feature of biotic stress and is observed both in compatible and incompatible plant-virus interactions (Hinrichs-Berger 1999;Díaz-Vivancos 2006). RONS act as signalling molecules as well as effectors of programmed cell death, which is involved in plant resistance (Lamotte 2005).…”

“…The characteristics of pathogen-induced "oxidative stress" (timing, concentration of RONS, etc.) differ among and within pathosystems and are strongly influenced by the momentary antioxidant capacity of the plant tissue (Love et al 2005;Díaz-Vivancos 2006;Sedlářová et al 2007). Both enzymatic and non-enzymatic antioxidant systems are involved in maintaining the levels and relative proportions of individual RONS molecules.…”

A Defense Associated Peroxidase from Lemon Having Dye Decolorizing Ability and Offering Resistance to Heat, Heavy Metals and Organic Solvents

“…The peroxidases belonging to PCOX superfamily exclusively contain animal peroxidases which have been suggested to be involved in the innate immunity, defense responses etc. [4]. The myeloperoxidase, eosinophil peroxidase, lactoperoxidase, etc.…”