ABOVE: This microscopy image shows a cross section of a liverwort infected with an oomycete pathogen (red).
PHILIP CARELLA
When Sebastian Schornack started his group in the Sainsbury Laboratory at the University of Cambridge in 2013, he was intrigued by the parallels between certain plant pathogens and the beneficial microorganisms that help plants extract nutrients from the soil. Symbiotic mycorrhizal fungi, for example, send branched structures called arbuscules into the host plant’s cells to trade water and minerals for carbohydrates such as sucrose. In a similar fashion, filamentous fungal and water mold pathogens extend finger-like haustoria into plant cells—but in this case, to help the invaders sap nutrients for their own reproduction.
In both scenarios, plants actively accommodate invasion by building a membrane around the structure projecting into the plant cell, and transporting materials to and from that interface. It seemed to Schornack that there were some basic “rules of engagement” ...
