Abstract

How immune responses are activated and regulated is a central question in immunology. In addition to molecular signaling, recent work has shown that physical forces regulate the immune response of vertebrates by modifying transmembrane protein conformation and cell contact. Mechanical stress and strain produced by forces constitute physical cues perceived by cells instructing gene expression. Whether mechanical cues generated by pathogens during host colonization can trigger adaptive responses in plant cells remains elusive. We found that local and progressive variations of plant cell wall tension caused by fungal pathogen attacks are transmitted to neighboring healthy tissue around the infection site and trigger immunity in distal cells. This thigmoimmunity process requires the reorganization of cortical microtubules and contributes strongly to Arabidopsis disease resistance. One-Sentence SummaryActivation of plants immunity depends on fluctuations of mechanical tension caused by a fungal pathogen.