The phosphatase PP2C12 is a negative player in LRX-RALF-FER-mediated cell wall integrity sensing

Hou, X.; Bender, K. W.; Guerin, A.; Kadler, G.; Gupta, S.; Haefliger, M.; Diet, A.; Roffler, S.; Campanini, D.; Wicker, T.; Zipfel, C.; Ringli, C.

doi:10.1101/2024.11.05.622083

bioRxiv · 10.1101/2024.11.05.622083

The phosphatase PP2C12 is a negative player in LRX-RALF-FER-mediated cell wall integrity sensing

Hou, X.·Bender, K. W.·Guerin, A.·Kadler, G.·Gupta, S.·Haefliger, M.·Diet, A.·Roffler, S.·Campanini, D.·Wicker, T.·Zipfel, C.·Ringli, C.

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Abstract

Plants have evolved an elaborate cell wall integrity (CWI) sensing system to monitor and modify cell wall formation. LRR-extensins (LRXs) are cell wall-anchored proteins that bind RAPID ALKALINIZATION FACTOR (RALF) peptide hormones and induce compaction of cell wall structures. At the same time, LRXs form a signaling platform with RALFs and the transmembrane receptor kinase FERONIA (FER) as a means to relay changes in CWI to the protoplast. LRX1 of Arabidopsis thaliana is predominantly expressed in root hairs and lrx1 mutants develop defective root hairs. Here, we identify a regulator of LRX1-RALF-FER signaling as a suppressor of the lrx1 root hair phenotype. The repressor of lrx1_23 (rol23) gene encodes PP2C12, a type 2C phosphatase of clade H that interacts with FER and dephosphorylates Thr696 in the FER activation loop in vitro. The LRX1-related function of PP2Cs appears clade H-specific and was not observed for other PP2Cs investigated. Collectively, our data suggest that LRX1 acts upstream of the RALF1-FER signaling module and PP2C12 has an inhibitory activity via modulating FER activity to fine-tune CWI signaling.

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Hou, X., Bender, K. W., Guerin, A., Kadler, G., Gupta, S., Haefliger, M., Diet, A., Roffler, S., Campanini, D., Wicker, T., Zipfel, C., Ringli, C.. 2024-11-06. The phosphatase PP2C12 is a negative player in LRX-RALF-FER-mediated cell wall integrity sensing. https://doi.org/10.1101/2024.11.05.622083

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