Overexpression of NDR1 Leads to Pathogen Resistance at Elevated Temperatures. Arabidopsis thaliana

Global climate change influences a myriad of plant-related processes, including growth, development, and the establishment and sustained interaction(s) with microbes. In the case of the latter, elevated temperature has emerged as a key factor that underpins the balance between host resistance and pathogen virulence. As a driver of this signaling mechanism, the role of plant hormones in both surveillance and signaling has emerged as a point of intersection between plant-abiotic and -biotic response. In the current study, we describe a role for NON-RACE-SPECIFIC DISEASE RISISTANCE1 (NDR1) by exploiting effector-triggered immunity (ETI) to define the regulation plant response to both pathogen infection and elevated temperature. We generated time-series RNA sequencing data of WT Col-0, NDR1 overexpression line, and ndr1 and ics1-2 mutant plants under elevated temperatures. Strikingly, the NDR1-overexpression line showed genotype-specific gene expression related to defense response and immune system function. Furthermore, the NDR1-overexpression line maintained immunity in response to infection by the Gram-negative bacterial phytopathogen Pseudomonas syringae by reducing type-III effector translocation, stabilizing the R-protein signaling complex, and sustained expression of SA biosynthesis genes at elevated temperature during ETI. The results described herein support a role for NDR1 in maintaining cell signaling during simultaneous exposure to elevated temperature and avirulent pathogen stressors.