Arabidopsis PIEZOintegrates magnetic field and blue light signaling to regulate root growth

The mechanosensitive ion channel PIEZO is known to play a role in root growth. However, whether thePIEZOgene responds to magnetic fields and the mechanisms underlying its regulation of root growth remain unclear. Here, we demonstrate thatArabidopsis PIEZOregulates root growth in response to both MF and blue light. Mutation ofPIEZOled to a significantly shorter roots under MF exposure and blue light illumination. We further identified thatPIEZOexpression in root tips was up-regulated by a blue light-induced signal, which is transmitted from leaves to roots in the presence of a MF.PIEZOmodulated calcium ion efflux and disturbed auxin transport, specifically through interactions with PIN-FORMED (PIN) 3, 6 and 7 under combined MF and blue light conditions. Notably, the blue light receptors CRYPTOCHROME 1 (CRY1) and CRY2 were essential for both MF perception and the regulation of root growth. Transcriptome analysis of thepiezo-clmutant under MF and blue light revealed that thePIEZOintegrates multiple signaling pathways, including those involved in gibberellin 4 (GA4), ethylene, calcium ion-related genes, mechanosensors, and microRNAs. Specifically,miR5648-5pexpression conferred MF sensitivity and provided a mechanism for the negative regulation ofPIEZOunder these conditions. Our findings elucidate a multifactorial mechanism by whichPIEZOcoordinates root growth responses to MF and blue light, integrating phytohormone signaling, mechanosensation, calcium ion dynamics, and light perception. This study highlightsPIEZOas a central node in a complex network that converges diverse environmental cues to regulate root growth.