This release is available in German.
Plants, too, have an immune system that protects them against diseases. The early detection of pathogens and the subsequent immune response, in particular at the cell wall, work as a protective shield. However, the pathogens that cause plant diseases have their weapons, too. Some are able to suppress the natural cell wall reaction in plants. "One particularly ingenious attacker, powdery mildew, can even reprogram cells in such a way that they adapt their architecture and metabolism to accommodate the fungus. The plant thus actively fosters the in-growth of the harmful mildew and even supplies it with nutrients," explains Prof. Ralph Hckelhoven from the TUM Chair of Phytopathology. How the mildew manages this manipulation and which plant components are involved in the process is still largely shrouded in mystery.
Hckelhoven's team of researchers has now succeeded in unraveling a part of the mystery. With the support of colleagues from Gatersleben, Gieen and Erlangen, the Weihenstephan scientists identified two proteins in barley that powdery mildew takes advantage of during its "hostile takeover" of living plant cells. Together, the two protein substances steer development processes in the plant cell. In barley, for instance, they are responsible for the growth of root hairs. The one protein, called RACB, is a molecular switch, which reacts to signals from outside to initiate a structural and metabolic response in the plant cells. In particular, it is involved in enlarging the plant cell surface during the growth process. The other protein, called MAGAP1, serves as its counterpart and can prevent or locally limit these activities in the cell.
The researchers observed just how the RACB protein supported the fungus during plant in-growth. A basic function of the protein, increasing the surface of the plant cell
|Contact: Jana Bodicky|
Technische Universitaet Muenchen