Plants are exposed to a wide range of abiotic and biotic stresses like influence of toxic substances or pathogen
attack. They have evolved highly sensitive mechanisms to perceive environmental changes, signal them from cell
to cell and respond rapidly to defend themselves or gain maximum advantage from the situation. The very large
enzyme family of UDP-glycosyltransferases (UGTs) plays a significant role in such adaptation processes.
The here presented project shall shed more light on the possible role of UGTs in, on the one hand detoxification of
toxic substances and on the other hand plant development. Professor Dianna Bowles (University of York, Great
Britain), who will host this work, has contributed significantly to the characterisation of these enzymes. Her group
uses Arabidopsis thaliana, applied by geneticist to investigate molecular and biochemical processes in plants, as a
model to analyse the function of these proteins. During my Ph.D. thesis I could show that UGT73C5, one of 118
members of the Arabidopsis UGT-family, is able to detoxify mycotoxins produced by pathogenic fungi of the
genus Fusarium, most likely to inhibit the plants immune response. The same enzyme seems to also regulate
activity of brassinosteroids, a class of phytohormones, and therefore potentially contributes not only to toxin
resistance but also to the regulation of developmental processes in plants. The apparently complex role of
UGT73C5 and the regulation of processes that lead to production of the protein in Arabidopsis shall be
investigated in the course of this project.
Knowledge obtained during this work may contribute to the understanding of the function of this family of proteins
in plants.