Understanding how plants regulate ion uptake and transport could have significant implications for plant nutrition and human
health. For example, by modifying ion uptake and transport, it is possible to develop crops that grow efficiently on nutrient-poor
soils, which will reduce the need for fertilizers, increase productivity and better nutritional value. The main research theme is
centered on magnesium deficiency in two model plants: Arabidopsis thaliana and Beta vulgaris (sugar beet). The overall goal is to
understand how these plants acquire, distribute and regulate their internal Mg level. In a physiological approach, mineral profile,
photosynthetic activity and sugar transport are analyzed during Mg deficiency. In a molecular approach, transcriptome changes are
identified in response to Mg deficiency. The transcriptional profiling allows the identification of genes involved in rapid
responses to external Mg deprivation. In addition, we are identifying limiting steps in sucrose loading from source organs (his transport
being often modified upon major elements deficiency). We are characterizing changes in sucrose transport activity by direct
transport measurements in purified membrane vesicles, and changes in the expression of sucrose transporter genes, as well as protein
abundance are examined. We also investigate the processes by which mineral nutrients, depending on their availability, can have
positive and negative effects on the development and growth of roots. We make use of a forward genetic approach to identify Arabidopsis
mutant plants that have lost their ability to respond to external mineral supply.