The fungus Piriformospora indica colonizes the roots of different plants. This can be orchids, tobacco, barley or even moss. It penetrates into the roots, but does not damage the plants. On the contrary, it can even promote the growth of its plant partners. Such and other interactions between the fungus and its partners are already known to the scientific community.
Research groups from Cologne and Würzburg are now reporting a new facet of the fungus-plant relationship in Nature Communications: The researchers identified a protein with which the fungus suppresses the immune defence of the populated plants. So it makes sure that it is not attacked like disease-inducing fungi and the relationship can succeed in the long run.
The protein "Fungal Glucan Binding 1" (FGB1) prevents the plant from producing an "oxidative burst". This usually generates aggressive oxygen radicals, which destroy potential pathogens and activate the immune system of the plant.
Protein makes the plant blind to fungus structures
How does the protein lame the immune response of the plant? "It binds with highly affinity and very specifically to sugar molecules that sit in the cell wall of the fungi and which are normally recognized as 'foreign' by the plant," explains Professor of Molecular Biology Alga Zuccaro from the University of Cologne. FGB1 acts like a camouflage coat and conceals the foreign sugar molecules from the immune system.
Via Francis Martin, Jean-Michel Ané