In: Phyton 61 (2021): S. 1-10; DOI: 10.12905/0380.phyton60-2021-0001; published online on 20 September 2021
This publication is dedicated to Professor Maria Müller on occasion of her 60th birthday
Subcellular quantification of glutathione concentrations during ZYMV-infection based on high resolution 3D reconstructions
Bernd Zechmann, Stefan Möstl & Günther Zellnig
with 2 figures and 2 tables
Key words: Cucurbita, glutathione, subcellular quantification, chloroplast, transmission electron microscopy (TEM), Zucchini Yellow Mosaic Virus (ZYMV).
Zechmann B., Möstl S. & Zellnig G. 2021. Subcellular quantification of glutathione concentrations during ZYMV-infection based on high resolution 3D reconstructions. – Phyton (Horn, Austria) 61: 1–10, with 2 figures and 2 tables.
Glutathione is an important antioxidant in plants and involved in activating plant defense and the development of resistance during biotic stress. While some information about changes in the subcellular distribution of glutathione during virus infection in plants is available, data on subcellular glutathione concentrations in plants during pathogen infection are lacking. In this study we developed a cytohistochemical and biochemical approach of glutathione labeling and visualization by TEM with 3D measurements of cell volumes by transmission electron and light microscopy. This method allowed for the calculation of subcellular glutathione contents in mM concentration in all cell compartments simultaneously in one experiment during Zucchini Yellow Mosaic Virus (ZYMV)-infection in pumpkin (Cucurbita) plants.
Results of this study showed a general increase of glutathione in ZYMV-infected leaves of 18 %. On the subcellular level an increase in glutathione contents in chloroplasts, nuclei, peroxisomes and the cytosol between 25 % and 150 % was observed. These data highlight the importance of glutathione in the protection of plants against ZYMV-infection. Highest glutathione contents (7 mM) were found in mitochondria of control plants. ZYMV-infection significantly decreased glutathione contents (–28.5 %) in mitochondria which could be related to the development of symptoms such as yellowing and mosaic pattern on the leaves. The physiological significance of these results is discussed in this paper.
We can conclude that the method applied in this study is well suited to measure subcellular glutathione concentrations during pathogen attack in plants.