Oxidative Stress

oxidizing agentReactive Oxygen Species (ROS), causing oxidative stress, were long considered as harmful by-products of (diseased) metabolism. However, recently they have emerged as important regulators of plant stress responses.

Perturbation in ROS production and/or scavenging are sensed by plant cells as a ‘warning’ message, and genetic programs leading to stress acclimation or cell death are switched on. Knowledge on regulatory events during ROS signal transduction is now only scratching the surface. Through combined top-down and bottom-up genomics and proteomics approaches we are dissecting the gene network governing ROS signal transduction in plants and pinpoint genes that are potential candidates for innovative molecular breeding strategies to develop stress-tolerant crops.

Catalase 2 (cat2) T-DNA insertion mutants are sensitive to excess light exposure and exhibit clear cell death and chlorosis

Arabidopsis thaliana Col-0 wild type, cat2-1 and cat2-2 mutant seedlings are germinated and grown under four weeks of long day conditions (i.e. 16 hours of light/8 hours darkness, 80 µmol m-2 s-1 of light intensity, temperature of 21°C and 50% humidity), in an air atmosphere where the concentration of CO2 is raised to 3000ppm. When catalase mutants are grown under high CO2, the photorespiratory glycolate oxidase activity is negligible. Hence, they show no signs of oxidative stress and are phenotypically indistinguishable from the wild-type Col-0. Subsequently, the plants are continuously exposed to a growth condition with excess light (i.e. 24 hours of light/0 hours darkness, 800 µmol m-2 s-1 of light intensity, temperature of 21°C and 50% humidity) for 48 hours, under a normal atmospheric concentration of CO2 (360ppm). Pictures of the plants were taken on a regular base with an interval of 10 min and combined to a movie, which starts around the 12th hour of excess light treatment. The catalase mutants start to display cell death and chlorosis after +/- 16 hours of excess light exposure."

Further reading

Jacques S., Ghesquière B., De Bock P.-J., Demol H., Wahni K., Willems P., Messens J., Van Breusegem F. and Gevaert K. (2015). Protein methionine sulfoxide dynamics in Arabidopsis thaliana under oxidative stress. Mol. Cell. Proteomics 14, 1217-1229.

Akter S., Huang J., Bodra N., De Smet B., Wahni K., Rombaut D., Pauwels J., Gevaert K., Carroll K., Van Breusegem F. and Messens J. (2015). DYn-2 based identification of Arabidopsis sulfenomes. Mol. Cell. Proteomics 14, 1183-1200.

Waszczak C., Akter S., Jacques S., Huang J., Messens J.* and Van Breusegem F. (2015). Oxidative post-translational modifications of cysteine residues in plant signal transduction. J. Exp. Bot. 66, 2923-2934.

Kerchev P., Mühlenbock P., Denecker J., Morreel K., Hoeberichts F.A., Van Der Kelen K., Vandorpe M., Nguyen L., Audenaert D. and Van Breusegem F. (2015). Activation of auxin signalling counteracts photorespiratory H2O2-dependent cell death. Plant Cell Environ. 38, 253-265.

Vermeirssen V., De Clercq I., Van Parys T., Van Breusegem F. and Van de Peer Y. (2014). Arabidopsis ensemble reverse-engineered gene regulatory network discloses interconnected transcription factors in oxidative stress. Plant Cell 26, 4656-4679.

Kerchev P.I., De Clercq I., Denecker J., Mühlenbock P., Kumpf R., Nguyen L., Audenaert D., Dejonghe W. and Van Breusegem F. (2014). Mitochondrial perturbation negatively affects auxin signaling. Mol. Plant 7, 1138-1150.

De Clercq I., Vermeirssen V., Van Aken O., Vandepoele K., Murcha M.W., Law S.R., Inzé A., Ng S., Ivanova A., Rombaut D., van de Cotte B., Jaspers P., Van de Peer Y., Kangasjärvi J., Whelan J. and Van Breusegem F. (2013). The membrane-bound NAC transcription factor ANAC013 functions in mitochondrial retrograde regulation of the oxidative stress response in Arabidopsis. Plant Cell 25, 3472-3490.