Project R-2077

Fructans and sucrose: a role in vacuolar antioxidant mechanisms? (Research)

The project aims at the following 3 specific goals by an intimate collaboration between The Lab of Molecular Plant Physiology (MPF, K.U.Leuven: fructans, fructan enzymes, protoplast and vacuole work). The research Unit Environmental Biology (EB, Prof. Vangronsveld, Prof. Cuypers, UHasselt: classic antioxidants with focus on heavy metal stress) and The Laboratory of Plant Systematics (LPS, KULeuven, Prof. Geuten: VIGS): 1. Develop Virus Induced Gene Silencing (VIGS) or Post Transcriptional Gene Silencing (PTGS) procedures to silence the 1-SST initiator enzyme in chicory (LPS). A classic genetic approach will be used to obtain mutant wheat 1-SST (m1-SST) plants. Study the phenotypes of these silenced 1-SST (s1-SST) plants under various stresses (drought, cold, heavy metal and other oxidative stresses) in comparison with control plants (MPF). This will show the benefit of fructan versus sucrose accumulation under stress. 2. Check the in vitro ROS scavenging activity of fructans in comparison with other sugars, vacuolar and reference compounds (MPF, collaboration). Test putative synergistic effects upon adding phenolic compounds. Identify and characterize sugar radicals or derived polymerization products in vitro and detect the same compounds in planta. 3. Experimentally test the hypothesis as by measuring all key role players (products, enzyme activities) on intact tissues, protoplasts, vacuoles and tonoplasts derived from s1-SST/m1-SST and control plants (MPF and EB). Time-permitting: studies on tonoplastic NADPH oxidases in Arabidopsis (gene expression, enzyme activity), including membrane composition and stability measurements.

01 January 2010 - 31 December 2013