The role of sulfotransferase proteins in the glucosinolate biosynthesis of Arabidopsis thaliana

• Applicant: Professorin Dr. Jutta Papenbrock
• Subject Area: Plant Biochemistry and Biophysics
• Term: from 2010 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 165972470

All members of the sulfotransferase (SOT, EC 2.8.2.-) protein family use 3’-phosphoadenosine 5’-phosphosulfate as sulfuryl donor and transfer the sulfate group to an appropriate hydroxyl group of several classes of substrates. The fully sequenced genome of Arabidopsis thaliana contains in total 21 genes that are likely to encode SOT proteins. Most of the substrates, and therefore the physiological roles, of plant SOT proteins are not known. Three of them catalyze the last step of glucosinolate (GL) biosynthesis. We would like to continue the in vitro characterization of recombinant desulfo (ds)-GL SOT proteins from different Arabidopsis ecotypes. One focus in these studies is to learn more about the reaction mechanism. Additionally, a three-dimensional structure of a SOT protein can help to understand why the isoforms have different substrate specificities. Furthermore the role of ds-GL AtSOT proteins has to be confirmed in vivo by the analysis of different plant mutants. Therefore the GL pattern will be analysed in available T-DNA insertion and in ds-GL AtSOT RNAi mutants. The results could lead to a better understanding of GL metabolism in Arabidopsis. A transfer of insights from the model system Arabidopsis will be transferred on the crop plant Brassica napus.

• DFG Programme: Research Grants