Schweighofer, Alois Kazanaviciute, Vaiva Scheikl, Elisabeth Teige, Markus Doczi, Robert Hirt, Heribert Schwanninger, Manfred Kant, Merijn Schuurink, Robert Mauch, Felix Buchala, Antony J. Cardinale, Francesca Meskiene, Irute 2007-07-13 Wound signaling pathways in plants are mediated by mitogen-activated protein kinases (MAPKs) and stress hormones, such as ethylene and jasmonates. In <i>Arabidopsis thaliana</i>, the transmission of wound signals by MAPKs has been the subject of detailed investigations; however, the involvement of specific phosphatases in wound signaling is not known. Here, we show that AP2C1, an <i>Arabidopsis</i> Ser/Thr phosphatase of type 2C, is a novel stress signal regulator that inactivates the stress-responsive MAPKs MPK4 and MPK6. Mutant <i>ap2c1</i> plants produce significantly higher amounts of jasmonate upon wounding and are more resistant to phytophagous mites (<i>Tetranychus urticae</i>). Plants with increased AP2C1 levels display lower wound activation of MAPKs, reduced ethylene production, and compromised innate immunity against the necrotrophic pathogen <i>Botrytis cinerea</i>. Our results demonstrate a key role for the AP2C1 phosphatase in regulating stress hormone levels, defense responses, and MAPK activities in <i>Arabidopsis</i> and provide evidence that the activity of AP2C1 might control the plant's response to <i>B. cinerea</i>. application/pdf https://folia.unifr.ch/global/documents/300439 https://folia.unifr.ch/documents/300439/files/buchala_ptp.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1105/tpc.106.049585 info:eu-repo/semantics/openAccess License undefined The Plant Cell. - 2007, vol. 19, no. 7, p. 2213-2224 info:eu-repo/classification/udc/57 The PP2C-type phosphatase AP2C1, which negatively regulates MPK4 and MPK6, modulates innate immunity, jasmonic acid, and ethylene levels in Arabidopsis http://purl.org/coar/resource_type/c_6501