Regulation der Funktion/Aktivität von Proteinen in Pflanzen durch S-Nitrosylierung

• Applicant: Privatdozent Dr. Christian Lindermayr
• Subject Area: Plant Physiology
• Term: from 2006 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 23631096

Nitric oxide (NO) is a free radical molecule that plays important roles in the regulation of cell function. A major action of NO is S-nitrosylation of protein cysteine residues. This modification regulates many different physiological processes in animals. Recently, I veri-fied the principle of S-nitrosylation in plants. S-nitrosylation was demonstrated for stress- and redox-related as well as metabolic proteins (Lindermayr et al., 2005; Lindermayr et al., submitted). The latter group contains enzymes providing S-adenosylmethionine for trans-methylation reactions and for the synthesis of polyamines and the plant hormone ethylene, which is involved in plant stress responses. Here, I want to investigate the regulation of the methylmethionine cycle by NO. S-Nitrosylation of methionine adenosyltransferase has al-ready been demonstrated and I want to continue to verify and characterize S-nitrosylation of other key components of this pathway. Studies on S-nitrosylation shall involve work on recombinant (and site-directed modified) enzymes as well as in vivo treatments of Arabidopsis wt and insertion lines mutated in NO-metabolism with pathogens and NO. These studies will have significant impact on our understanding of NO-regulated processes in plants and on the crosstalk between NO- and ethylene-dependent signalling pathways.

• DFG Programme: Research Grants