Comparison of Light Condition-Dependent Differences in the Accumulation and Subcellular Localization of Glutathione in Arabidopsis and Wheat

Abstract

This study aimed to clarify whether the light condition-dependent changes in the redox state and subcellular distribution of glutathione were similar in the dicotyledonous model plant Arabidopsis (wild-type, ascorbate- and glutathione-deficient mutants) and the monocotyledonous crop species wheat (Chinese Spring variety). With increasing light intensity, the amount of its reduced (GSH) and oxidized (GSSG) form and the GSSG/GSH ratio increased in the leaf extracts of both species including all genotypes, while far-red light increased these parameters only in wheat except for GSH in the GSH-deficient Arabidopsis mutant. Based on the expression changes of the glutathione metabolism-related genes, light intensity influences the size and redox state of the glutathione pool at the transcriptional level in wheat but not in Arabidopsis. In line with the results in leaf extracts, a similar inducing effect of both light intensity and far-red light was found on the total glutathione content at the subcellular level in wheat. In contrast to the leaf extracts, the inducing influence of light intensity on glutathione level was only found in the cell compartments of the GSH-deficient Arabidopsis mutant, and far-red light increased it in both mutants. The observed general and genotype-specific, light-dependent changes in the accumulation and subcellular distribution of glutathione participate in adjusting the redox-dependent metabolism to the actual environmental conditions.

Light Intensity- and Spectrum-Dependent Redox Regulation of Plant Metabolism

“…Under high PPFD stress, H 2 O 2 accumulation in chloroplasts can be scavenged by AsA, GSH, and APX activity, in the cytosol and peroxisomes by AsA, GSH, APX, and CAT activities, and in vacuoles by AsA and POD (EC 1.11.1.7) activities ( Figure 3 ) [ 99 , 105 , 106 , 107 ]. AsA concentration rises with increasing light intensity, and AsA recycling has been localized in peroxisomes, mitochondria, and the cytosol [ 108 ].…”

Differences in the light‐dependent changes of the glutathione metabolism during cold acclimation in wheat varieties with different freezing tolerance

“…It suppressed their activity even before cold in the two tolerant genotypes, which could lead to a more oxidising redox environment and initiate redox‐dependent adaptive processes being observed in normal light intensity only during cold. The influence of light intensity on the antioxidant system was also shown in maize and Arabidopsis (Gasperl et al, 2021; Szalai et al, 2009). This effect greatly contributes to the induction of the cold acclimation process by high light intensity (Janda et al, 2014).…”

“…Then, the seedlings were grown on half-strength modified Hoagland medium (changed on every 2 nd day) for 14 days at 75% relative humidity and 20/17°C day/night temperature, with 16 h illumination during the whole experiment in order to obtain a more pronounced effect of light conditions (Kocsy et al, 2000a). The following three light conditions were used from the beginning of the growth in hydroponics (in the same growth chamber with one LED-panel divided into three parts): white light at 250 µmol m − ² s −1 (referred to as normal light intensity, blue/red ratio of 1:2 combined with red/far-red ratio of 10:1); white light at 500 µmol m − ² s −1 (referred to as high light intensity, blue/red ratio of 1:2 combined with red/far-red ratio of 10:1) and far-red light (blue/red ratio of 1:2 combined with red/far-red ratio of 10:1) at 250 µmol m − ² s −1 (Table S1, Figure S1) (Gasperl et al, 2021). Light modules were equipped with a continuous wide spectrum LED (Philips Lumileds, LXZ2-5790-y) and three narrow spectrum LED armatures with dominant wavelengths of 448 nm (Philips Lumileds, LXZ1-PR01, San Jose, CA, USA), 655 nm (Philips Lumileds, LXZ1-PA01) and 750 nm (Edison Edixeon, 2ER101FX00000001).…”

“…Previous studies indicated that light spectrum and intensity significantly influenced both the pool size and the redox state of glutathione in the leaves of wheat and Arabidopsis (Gasperl et al, 2021; Toldi et al, 2019). However, it was not clarified whether these changes depended on the synthesis or degradation of glutathione and differed during cold acclimation in genotypes with different levels of freezing tolerance.…”

“…At increasing altitudes, enrichment of the blue component in white light was accompanied by a larger ASA content in alpine plant species (Wildi & Lutz, 1996), and it induced the antioxidants in Rehmannia glutinosa grown under controlled conditions (Manivannan et al, 2015). A considerable reduction in the R/FR ratio resulted in a large decrease in the amount of antioxidants in the shade leaves of bean (Bartoli et al, 2009) and increased the glutathione disulphide/glutathione (GSSG/GSH) ratio in wheat leaves grown under optimal light intensity both in extracts and at subcellular level (Gasperl et al, 2021; Toldi et al, 2019). High light intensity had a similar effect on the redox state of glutathione in wheat (Toldi et al, 2019).…”