Communication Between Filamentous Pathogens and Plants at the Biotrophic Interface.

Fungi and oomycetes that colonize living plant tissue form extensive interfaces with plant cells in which the cytoplasm of the microorganism is closely aligned with the host cytoplasm for an extended distance. In all cases, specialized biotrophic hyphae function to hijack host cellu-lar processes across an interfacial zone consisting of a hyphal plasma membrane, a specialized interfacial matrix, and a plant-derived mem-brane. The interface is the site of active secretion by both players. This cross talk at the interface determines the winner in adversarial rela-tionships and establishes the partnership in mutualistic relationships. Fungi and oomycetes secrete many specialized effector proteins for controlling the host, and they can stimulate remarkable cellular reorga-nization even in distant plant cells. Breakthroughs in live-cell imaging of fungal and oomycete encounter sites, including live-cell imaging of pathogens secreting fluorescendy labeled effector proteins, have led to recent progress in understanding communication across the interface. [ABSTRACT FROM AUTHOR]