NPR1 and infection: NPR1 is a central regulator of systemic acquired resistance, a systemic response to pathogen infection that does not induce cell death, but leads to an increase in salicylic acid content, which in turn upregulates EDS1 and EDS5 expression28, 29, 30, similar to the incompatible phenotype in Capsella. Expression analysis indicated that NPR1 was not robustly differentially expressed between NIL(2rr; 7rr) and NIL(2gg; 7gg) plants (Fig. 2c), suggesting that the incompatibility is due to differences in the coding sequence.