TY - JOUR T1 - Pattern-triggered immunity and cell wall integrity maintenance jointly modulate plant stress responses JF - bioRxiv DO - 10.1101/130013 SP - 130013 AU - Timo Engelsdorf AU - Nora Gigli-Bisceglia AU - Manikandan Veerabagu AU - Joseph F. McKenna AU - Frauke Augstein AU - Dieuwertje van der Does AU - Cyril Zipfel AU - Thorsten Hamann Y1 - 2017/01/01 UR - http://biorxiv.org/content/early/2017/04/26/130013.abstract N2 - All plant cells are surrounded by walls, which must often meet opposing functional requirements during plant growth and defense [1–3]. The walls meet them by activating cell wall signaling processes to modify structure/composition in a controlled manner. Such adaptive changes have been summarily described as cell wall plasticity and identified as major obstacle to knowledge-based modification of lignocellulosic biomass [4]. Plasticity requires activity of the cell wall integrity (CWI) maintenance mechanism [5,6]. This mechanism monitors the functional integrity of the cell wall and initiates compensatory processes upon cell wall damage (CWD). To date, neither the mode of action of the CWI maintenance mechanism nor its’ role in immunity are understood. We investigated the mechanism in Arabidopsis thaliana and found that CWD caused by different means induced similar, turgor-sensitive responses, suggesting similar principles underlie all CWD responses. Genetic analysis found that the receptor-like kinase (RLK) FEI2 and the plasma membrane channel MCA1 function downstream of the RLK THE1. Phenotypic clustering with 24 genotypes identified a core group of RLKs and ion channels required for activating CWD responses. By contrast, responses are repressed by pattern-triggered immune signaling components including PEPR1 and 2, receptors for the plant immune signaling peptide AtPep1 [7]. AtPep1 application repressed CWD-induced phytohormone production in wildtype, but not in pepr1/2 seedlings. These results suggest that pattern-triggered immunity suppresses responses triggered by the CWI maintenance mechanism through AtPep1 / PEPR1/2-dependent signaling. However, if pattern-triggered immunity is impaired, the repression of CWI-regulated responses is removed thus compensating for immunity impairment. ER -