Plant immunity comes at a price
Plants are under permanent attack by a multitude of pathogens. To win the battle against fungi, bacteria, viruses and other pathogens, they have developed a complex and effective immune system. And just as in humans, this can also overshoot its target when some of the plant's own proteins are mistakenly identified as foreign. Such autoimmune reactions can lead to tissue defects and growth arrest, and is particularly apparent in hybrids, where two divergent immune systems meet. Scientists from the Max Planck Institute for Developmental Biology in Tübingen, Germany, have now pinpointed the most common culprits for autoimmunity. Surprisingly, these are components of the immune system itself, which are mistakenly recognized by other immune receptors as intruders.