Pathogen-derived mechanical cues regulate the spatio-temporal implementation of plant defense

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.

PERKing up our understanding of the proline‐rich extensin‐like receptor kinases, a forgotten plant receptor kinase family

“…These results suggest that some PERKs might perceive cell wall modifications through direct sensing of biomechanical stress. In line with this, the first PERK functionally studied was induced in response to mechanical stimuli and in response to Sclerotinia sclerotiorum , shown to exert plant cell wall tension (Silva & Goring, 2002; Léger et al ., 2021). Furthermore, it is noteworthy that many PERKs are involved in polar growth of root hairs and pollen tubes, a process requiring a fine‐tuned expansion of the cell wall (Bai et al ., 2009; Humphrey et al ., 2015; Hwang et al ., 2016; Borassi et al ., 2021).…”