Wednesday, May 9, 2018 at 12:20pm
Frank Van Breusegem
Ghent University, Belgium
Suboptimal growth conditions caused by drought, temperature, salt and pathogen-related stress are leading to worldwide yield losses in cultivated crops. It is anticipated that this problem becomes even bigger in the future, as climatic changes will cause more temperature and drought stress, and, in the meantime, the demand for plants for food, feed and bioenergy is increasing. This has encouraged the development of appropriate breeding strategies targeting stress tolerance and has made crop stress tolerance a major objective in plant biotechnology research.
Oxidative stress or the rise in reactive oxygen species (ROS) levels is associated with a multiple of cellular traumas in probably all living organisms (Mittler et al., 2011). Increased cellular ROS levels can originate from increased production rates through diverse oxidases and peroxidases or from overheated photosynthetic and respiratory electron transport chains. Like other organisms, plants are harnessed with a large and diversified battery of antioxidant mechanisms to detoxify diverse ROS.
Genetic perturbations of individual genes of the antioxidant network have demonstrated their key roles in keeping cellular ROS levels under control. Reactive Oxygen Species have recently 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 (De Clercq et., 2013). Knowledge on the regulatory events governing ROS signal transduction is however still scratching the surface. Through a combined top-down and bottom-up genomics approach 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 (Tognetti et al., 2010, Waszczak et al., 2014).
In addition, we study stress-related plant proteases and their inhibitors. In a recent study in collaboration with the Gevaert lab, for the first time in plants, a large scale collection of protease substrate proteins was described. From Arabidopsis thaliana seedling proteomes, several hundred substrates have been discovered for metacaspase 9 (AtMC9), giving novel insight into the role of AtMC9 in seedling development and lightning new exciting avenues for future research (Tsiatisani et al., 2013).