NDR1 Sequencing

Arabidopsis (Arabidopsis thaliana) NON-RACE-SPECIFIC DISEASE RESISTANCE-1 (NDR1) is required for the activation of effector-triggered immunity (ETI) through the coiled-coil nucleotide binding-site leucine-rich repeat (CC-NB-LRR) class of resistance proteins. Previous work in our laboratory provided the first mechanistic understanding of a role for NDR1 through correlating a loss in the plasma membrane (PM)-cell wall (CW) adhesion with an increase in susceptibility to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). Herein, we build upon these analyses to define the link between biotic and abiotic stress response activation mediated by NDR1. Using NDR1 as a tractable marker for the activation of ETI and PTI, we identified a role for NDR1 in drought stress tolerance, which is mediated in large part by the modulation of guard cell dynamics. Using stomata function as a convergence point in our analyses, we observed that stomata closure in the ndr1-1 mutant was abrogated following treatment with both ABA, drought and the PAMP flg22. In total, our data suggest that NDR1 mediates crosstalk between abiotic and biotic stress signaling.