A pair of chitosan receptors confer broad-spectrum fungal resistance.

OsFID1 and OsFID2 form a conserved receptor complex that confers broad-spectrum fungal resistance in land plants.

• Why it matters: Understanding how plants perceive chitosan, a key fungal cell wall component, is crucial for developing durable disease resistance strategies, as this perception mechanism was previously unknown.
• What they did: The study identified OsFID1, a DUF26 domain protein, as a chitosan-binding receptor that partners with OsFID2, a kinase, to mediate immune responses in plants, with OsFID2 phosphorylation being essential for function; homologs are conserved across land plants, including monocots and dicots.
• The result: Ectopic expression of OsFID1 in wheat and maize enhanced fungal resistance without affecting growth, suggesting this receptor complex could be exploited to engineer broad-spectrum fungal resistance in crops.