Wall-Associated Kinases Participate in Defense Against Rice Blast

Wall-associated kinases (WAKs) have been shown to be positive regulators of fungal disease resistance. Researchers from INRA and CIRAD led by Amandine Delteil developed rice (Oryza sativa) loss-of-function mutants of four selected Oryza sativa WAK genes (OsWAK), to determine if individual OsWAKs are required for resistance to the rice blast fungus, Magnaporthe oryzae.

While OsWAK14, OsWAK91 and OsWAK92 positively regulate quantitative resistance, OsWAK112d is a negative regulator of blast resistance. Researchers also found that early transcriptional regulation of rice OsWAK genes is triggered by chitin from fungal cell walls. OsWAK91 was also found to be required for H₂O₂ production to enhance defense gene expression during infection.

The rice OsWAK genes studied are part of basal defense response, potentially mediated by chitin from fungal cell walls. This work also shows that some OsWAKs may act as negative regulators of resistance.

 For more information on the study, read the article on BMC Plant Biology.