A sequential MAP kinase cascade regulates early mechanical signaling

ABSTRACT: Plants respond to mechanical stimulations such as wind, rain, touching or wounding to safeguard their development and survival. Rapid activation of Mitogen Activated Protein Kinases (MAPKs) by mechanical stimuli was already reported nearly 25 years ago, but the mechanism and function of this phenomenon has remained unknown. Here we report that mechanical stimulation activates a MAPKKK3/4/5-MKK4/5-MAPK3/6 cascade within 60 seconds, which leads to the induction of nearly 800 genes, encompassing the majority of the core early touch response. Most of these genes overlap with the touch-responsive genes regulated by CAMTA1/2/3, suggesting an interplay between MAPKs and CAMTA transcription factors. Furthermore, we found that loss of MKK4/5 leads to global impairment of touch-regulated protein phosphorylation, suggesting they are crucial regulators of touch-induced phosphorylation. On the other hand, we could not find clear evidence for a role of phosphorylation in the early activation of the touch-induced jasmonic acid (JA) signalling pathway, nor did loss of JA affect the overall early touch phosphoproteome. Lastly, the mkk4/5 mutant has a smaller reduction in rosette leaf size after touch treatment compared to wild type, indicating that MKK4/5 plays a partial role in thigmomorphogenesis but may have a larger contribution to activation of plant defense signalling. In summary, we have now identified a MAPKKK3/4/5-MKK4/5-MPK3/6 cascade as a key touch- and wounding signalling pathway in plants.

INSTRUMENT(S):

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Shoot

SUBMITTER: Tingting Zhu  

LAB HEAD: Ive De Smet

PROVIDER: PXD060728 | Pride | 2026-06-16

REPOSITORIES: Pride